That is really kind of you to say. Really kind. I'm told I have a lot going for me. I'm smart, attractive, funny, kind, compassionate, caring, ambitious etc. Or so I'm told lol. I just need to try and see that. I feel I've wasted my 20's due to my mental health so I don't see all the good things. But I've also been in abusive relationships. So that doesn't help.
Yes, I completely understand what you're saying there. I have also done the same, throughout my twenties (I am 28). Naturally, the more mistakes you feel you've made, the less respect you have for yourself and the less trust you have in applying your judgement in making future decisions. Seems like these past relationships have therefore taken your confidence. I actually believe they sound largely responsible for this lack of self-esteem. I don't believe you originally thought this about yourself, but they have changed your thinking. We start off fine and then people chip away at your confidence, for their own ends. By that, I mean that they clearly felt insecure because they knew you were above them, so panicked, and realised the only course of action was to try and bring you down to their level, to prevent you leaving. Of course, that could never realistically happen, not fully, so they created a 'smoke-screen' through manipulating you into believing you in fact had very little to offer and I suspect that they were doing you a 'favour'. Anything but, and that was their concern. They should have praised you, and sought to learn and grow from you, and become a better person. They rarely see that though.
If you accept that statement above, you'll realise the way they treated you was something of a warped compliment. I am so glad you're out that. Awful for you.
You said people often give you positive feedback. Again, people are rarely generous and hardly ever hand out ill-deserved compliments, so it must be true. I would absorb all of these by actively observing all the little acts of kindness I performed and really internalising them. I also think one of the reasons you don't notice all your positive qualities, is because you are only demonstrating them on other people and improving their lives - very few times turning them on yourself and using them to help you, so you don't fully appreciate their effect. With the ambition, I suppose that may be perfectionism creeping in. Many intelligent people never feel they've got anywhere, but they inevitably feel there is always 'further to go'. But, every achievement is a step closer.
You are likely more intelligent than most, too, as battling and winning over mental illness seems to activate parts of the brain that others aren't privy to. I have found.
Of course it'll take a while to build your confidence back up, but with some of these suggestions, to gradually introduce, and the unconditional support of a lovely partner, I have every faith you'll get there. He is great reinforcement and has nothing to gain in a nasty sense. Just seems to really love you. I know you'll get there.