I'm a heartbreaking monster pretender. I want to stop but I don't. Any insights?

TLDR; How to become more human? I'm a heartbreaker and I can't get out of my own ass to love another person or treat them like a human being. I'm too insecure and am not letting myself be strong enough to work in a relationship. I'm losing the love of my life and I regret it. How can I break this cycle? I "can't" stop being a bitch. I broke his heart for the last time, he deserves to be happy, I wanted to make our relationship work but I couldn't get past my own insecurities and selfishness. I don't even know if I truly love him yet I'm still here thinking about us for the past days and not going over to see him or say anything, leaving him all alone in his own heartbreak because of me. I've let him go but I want him so much. I know he still loves me but I am no good for him. I'm afraid of being loved and don't know how to accept it. Or am I pretending? Do I love this man? or am I just obsessed? I never let him see the real me for more than 5 minutes. I can only be nice for 5 minutes. I never felt safe, it isn't his fault. I just never took the leap to experience true love with him, or anyone. He's the closest to me ever, but I don't feel like he loves me. He didn't want to abandon me but I pushed him to insanity to where he has to save himself by being away from me. I want to change, but I don't. I read articles on how to have healthy relationships. I meditate about it, but when I've gone to see him, I just become a dumbass bitch cunt and give us all a hard time and nobody wins. I don't even know what I feel anymore and I just make it worse for us. I'm not even crying as I type this. I spent my previous days crying my eyes out already. Even more sad, I probably will stop caring if I don't go to talk to him in the next days. Or maybe it'll hit me like a truck and I regret it all. I already do. But even when I go see him, I can't think of anything to say and clam up and it just gets awkward like why did I even show up and it's just a waste of time. Do I just like his attention? He thinks I don't care about him. I'm not fit for relationships. I know he loves me but I feel pathetic to believe I could be loved, so I don't believe it. Obviously yeah, anyone who reads this may think we're better off separate, but has anyone ever been.. in a position like me? How did you deal with it? I can't take this loss, I won't have it. I need to change. Why do I feel it's so pathetic to be happy? I suppress everything I feel and act like everything's fine when it's not. I pretend things are ok and numb myself on the daily and it hurts him because I won't change and it hurts me too because I still keep hurting him and lose. I don't deserve anything with the way I am. I don't know if therapy can help. I feel I'll just forget and be like this again. Maybe I really don't care, huh? Am I really a monster? I feel like I am. I don't have a heart. I can only think and care for myself. I deserve to die with this way of thinking. I am in a dark place, but I like it here, except I'm suffering. I don't want to be like this anymore, how can I help myself to be better? I don't have anyone to go to. I hurt him too much for him to hear me say how shitty I am. I can't do anything for anyone like this. No song lyric can help me change. No amount of pain I've caused in him will help me change to be better for him. I give up. I quit. I'm a quitter, and quitters don't deserve any love. I did this to myself. I'm not being harsh either, it's the reality with this mindset. I'm a loser. and I don't have to be, but I'm so used to it I keep being it. I don't want to be like this anymore, but I might become like those haunted spirits for that one trauma they have, and it'd be my fault entirely for putting myself here. I can't be any more real with how shitty I am of a person. Thank you reddit for being here, but if anyone can provide insight, please help. I really need it... I might just kill myself for what I've done to him. I never cheated but I broke his heart by not being here. Not being a real lover who loves and cares for him. I neglected him hardcore to the max. I need to stop being a bitch and own up to my shit. Not sitting here talking to myself. It's pathetic, I let him down. I let everyone down that loves me, by being like this. I just don't stop. It's so easy though, right? But I'm retarded and dumb so I'll keep making these mistakes. I'm sorry. What is love anyway? Why do I feel so insecure with him about it? I love my friends but I don't feel insecure with them. Why do I have to feel insecure with my lover? and Why can't I tell him how I really feel? I fear I don't love him at all. I don't know what love is. and if I didn't love him, why am I so hung up on him for days? I can't eat, I can't sleep. I can't do anything. "Can't" in quotations for every word. I know, I CAN, but I don't. I'm insane. I want to suffer. It's all I'm used to. But I don't. I'm just a monster. I don't even like his friends. I don't care for friends. just one really friend is good enough. They talk about things I can't relate with, because I'm so closed off. Maybe we're not compatible. I know I'm not dating his friends but they are a huge part of the picture. I do like them but I don't try to connect as normal friends would. I'm just a bitch. But please send me some support, I want to make this work. I know it sounds like an uphill battle, but I don't want to lose this. We've been together for so long, 5 years now. But I've been like this for the longest time.. He's been so patient and loving and caring, but why don't I ever put in the effort? I'm just a bitch.. I'll never find anyone else as amazing like him. Help me.. Why am I like this.. I break my own heart, realizing how much of a monster I am. I know I need help, but please again, give me insight if you've gone through something similar.. I feel ashamed for saying all this.. I'd rather die than accept this reality. I need help. I've never been so low in my life. Just stop being a bitch, but I can't or don't. I've attached too strongly to my fears to stop.

1234567890 you're not a bad person stop beating yourself up. And you're not a monster. I want to say what I think might be your problem but I could definitely be wrong.

Reading all the things you've said and after all what I've read what you're describing sounds like bipolar disorder. I'm not a doctor nor am I in the field of medicine. My neighbors ex wife is bipolar and what you're describing almost fits to a T.