I guess that our situation isn't that uncommon unfortunately. I hope you'll also be able to improve your mind state similar to what I've done. I recommend reading PJ Ebys comments here on Less Wrong since he's mentioned a large amount of his important ideas in them. You can also PM me if you'd like.
Sorry for being late with my answer.
SASS is PJs terminology, it stands for Significance, Affiliation, Stability, and Stimulation. The exact categories aren't that critical, the important idea is that they represent the terminal values all humans seem to have hard wired into them so to speak.
So what I meant is that it's important to know why you're motivated into doing action X. If it is because you've learned that you'll gain SASS by doing X then everything is fine. That's operating under what PJ calls "positive motivation" and you'll feel as if you really want to do it and you can pursue X without feeling stressed out, by naturally selecting the best course of action, among other things.
If you're operating under a SASS threat on the other hand, which you do if you've learned that you'll lose SASS if you don't do X, then your mental state will be completely different. This is what he calls "negative motivation" and there you'll feel like you should and ought to do X without really feeling like you genuinely want to. It's usually accompanied by only doing as much of X as necessary to remove the immediate feeling of threat and then mostly feeling bad about not doing more even though you feel like you "could", "should", "ought" and similar feelings.
Considering my recent personal experience (which I mentioned here) with removing a huge hidden negative motivation from my life I'd say that the absolutely most critical thing is to find out why you want to save the world.
If you find out that it's actually because you feel some kind of SASS threat if you don't try to save the world, I'd strongly suggest trying to directly remove that feeling anyway. The risk here is of course that after you've done it, you might find out that you never actually wanted to save the world to begin with. However, considering how I've personally experienced the shift in identity from feeling like I should be a good person to feeling like I am a good person, and the much increased motivation in actually doing good it has brought with it, I suspect that the few people who'll realize that they don't actually want to save the world will be more then compensated by the much increased effectiveness of the people who'll go from feeling like they should be world-savers into feeling like they are world-savers.
This sounds very similar to the argument against atheism where the believer is afraid that he might start to do a whole bunch of horrible things if he'll no longer fear punishment from God.
What I've noticed in my case is that yes, I now do think I could feel like a good person even if I do bad things to others. However, I now genuinely don't want to hurt other people. In a way it feels like this is the first time in my life where I'm actually able to really care for and empathise with other people since I no longer have to be so preoccupied with myself.
Just wanted to add that I also felt very inclined to disengage with PJ on many occasions, something which I also did for long periods. That feeling was the very thing that kept me stuck and not being able to make a change.
Now from my new vantage point I can see what was going on. The crucial part was my rule that in effect said that I should start to feel like a bad person as soon as I started thinking about taking a major initiative on my own. It made me feel uncomfortable and I unconsciously felt an urge to find some kind of authority figure whom I could check the decision with to find out if it is okay to do.
So when PJ told me to give myself these rights, my brain automatically interpreted it as being a major initiative and therefore as a demand for doing something bad. I started dragging my feet and coming up with a whole bunch of bogus rationalizations for why I couldn't follow his request and when he didn't buy them and simply insisted that I'd do the technique, I instead started to feel kind of resentful and angry that he wouldn't listen to me or understand me. Sometimes I even started to feel a personal dislike towards him since my brain automatically jumped to the conclusion that since he's insisting that I'd do something that will make me feel bad, he obviously doesn't care about me and thinks I'm a bad person who deserves to feel bad.
Now I tried my best to constantly reflect about and rationally analyze these emotions when they came up but I can tell you that it's extremely hard to do when you're engulfed by them. I remember that often when I started to feel angry and frustrated I tried to ask myself something like:
"Is this feeling actually justified? Isn't this is just what you'd expect to feel based on your understanding of this process?"
Unfortunately if I'd fallen to deep into the emotion the answer I often got back was a kind of childish answer that stopped me from going further.
"But I'm angry with him! I don't wan't to let him get away with a bunch of unreasonable and uncaring demands!"
I actually just started to get my new identity at the end of last week. And the big realization that I'm allowed to feel like a good/likeable/worthwhile person no matter the circumstances was made just about 50 hours ago.
The reason you might get the impression that I've had it for a longer time is that for many months I've been pretty clear on what my new identity would be like on a rational level. I've been expecting many of my new behaviours to turn out as they've now did for example. The big difference is that now I finally get to know what it feels like to have this new identity, and of course, that I'm able to implement it in practice. :-)
And I agree in that I don't think I could have made this change without any kind of dramatic incident; I'm pretty sure that it would never have happened on it's own since my behaviour was stuck in a kind of stable equillibrium.
I suspect that another person could have triggered the change in me though by kind of forcing me through this process and not relenting even if I try to make them stop. I imagine that when then feeling completely exposed they could give me the basic need that I've always feared that I don't have and finally support me in realizing that I can give it to myself. This probably has to be done in person though so you can't easily get away.
The big problem is of course that if you're the person who's trying to help you have a huge responsibility for actually diagnosing the other persons problems correctly. Since it unavoidably is a traumatic process I can imagine how horrible it must feel if the person who forced you to completely expose yourself turned out to completely misunderstand what you actually feared.
I'm a member of his group so I've gotten personal assistance but what I've done is basically first diagnose my problems by using his so called RMI technique, which I'm pretty sure he's mentioned several times here in the comments, which basically just consists of sincerely questioning yourself about your problem and passively notice what comes to mind without trying to rationalize it away logically.
Through that technique I found out that I've unconsciously judged all my decisions in life for "goodness", that is I've constantly feared that I'll not be a good person if I make the wrong decisions. Unfortunately the number of rules for things which make me a bad person have been very large so I've basically lived a passive lonely life waiting for someone to come and tell me what to do. One particularly frustrating thing has been that I've felt that I'm a bad person if I actually try to take control over my life, and that includes using PJs methods, so for about six months I've been completely clear on what my problem is, how to solve it, believed that it would work on a rational level, but at the same time feeling completely uninterested in actually doing anything about it. The trigger for action was when my girlfriend broke up with me and I temporarily got into an emotional state where I felt that I had nothing to lose, and since I knew PJs techniques I managed to use the opportunity to break the deadlock.
The specific technique I used is his so called "rights work", which I also think he's mentioned here. You basically tell yourself that you have the right to feel feeling X even if condition Y is true. The big one for me was when I hit upon the phrase:
"I have the right to feel like a good person no matter what I do."
Realising that instantly made me start to cry what can best be described as tears of joy mixed up with some anger and indignation. Then after a couple of minutes it was over and now I feel like a completely different person. Or rather closer to the person I've always wanted to be but never felt I've been allowed to be. For example, writing this answer has been trivial whereas I've previously been a chronic lurker on all forums I frequent due to worrying about what everyone will think of my writings.
I've found out about PJ Ebys ideas and even though I just recently managed to use them to make a substantial change, I'm pretty sure it's the largest positive change in my entire life so far.
You seem to be saying that you find some peoples scope insensitivity to be more discusting than actual human suffering, but that seems like a perfect example of a pretty severe case of scope insensitivity in itself?