This message won't apply to all readers but it will for a surprisingly large number:
It's not your fault.
In your effort to avoid being one of the whiners and malcontents who blame everyone else for their troubles, you have traveled too far in the other direction. You've assumed that way too much is within your control and, hence, it is your fault if things are not turning out as they should.
A great many of those burdens that you carry would have happened no matter what you did. The people you think you could have changed and the events you assume you could have prevented would have turned out that way or close to it regardless of any additional cleverness or effort on your part.
Your desire to assume responsibility is admirable but the extreme that you've adopted is both crushing and unfair. You may disdain those who seek to avoid accountability and yet your decision to soak it up like a sponge is equally destructive. Your bag of self-reproaches is overflowing.
Start emptying it. You don't need to ascribe ownership of the blame to anyone else. You do need to stop assuming that it is yours.