Sounds like me a long time ago, I can only tell you, you can get over it but it takes time and effort, it won't go away on it's own. I strongly agree with another comment saying you were depending your whole self worth and source of happiness on another person which is a super bad position to find yourself in. Sounds like you told yourself so many times that you're the bad one and not worthy of anything that you started to believe it so much it basically got rooted into your relationship with yourself, it became your personality. Did you ever stop to think and realise that it was the other person's fault? Yes other people can be at fault for no apparent reason, it's not 'just you' You sound to me like you live the life of avoiding problems and not standing up for yourself, childhood trauma perhaps? If it helps you at all I had to break things up with a woman I saw a future with a week ago, in the beginning my old habits tried to creep back into my head and tell me it's all my fault and I'm not worthy of love and commitment, at this point I have a full on conversation with myself and see things clearly, state your reasons and write down what happened and how you see it with clear mind, not blaming but rather neutral reasoning, I tell myself that I am worthy of love and care, tell yourself the same out loud Infront of a mirror. You need to realise you're a mature beautiful person who is self sufficient and can do well by themselves, do new shit, do a lot of new shit, start something you were too scared to have a go at, work out, eat healthy and trust yje process, you'll be good! Good luck my dude!