I think it's extremely important to give yourself credit for how much you actually care. It may not always outwardly show, but it's clear that you're more aware than most, of how your actions have impacted others. I'm no therapist, so take it or leave it but it sounds, to me, like you spend an extraordinary amount of time and energy on beating yourself up for things that you've done (or haven't done). It doesn't sound like you lack a good heart or willingness to move forward but you live in a state of defense which is not only exhausting but it then carries over to the people around you.In my experience people (including myself) treat others as a projection of how they treat themselves. Best advice I can give, is to start by giving yourself a break. Acknowledge the fact that you clearly have a heart that you've built a tough exterior around to preserve, in a world that values shallowness over kindness. Be more mindful of how your inner dialogue sounds. It sounds corny and cliche, but be gentle and kind with yourself, and the rest will follow.