Never ending thoughts.

Hi all, trust you are doing well? I am manic bipolar, suffer from ptsd and the list goes on, I am on medication and it does work in terms of coping with anxiety and so on. I know I still have to rewire my brain and think positive, no meds or doctor or support can fix it, so I am fully aware that I am responsible for my own being and mindset. I tend to get upset very quickly and I am very sensitive, most of the time I would wake up in a depressive mood for no reason at all really, or I'll wakeup angry and irritated, still no reason, whenever this happens I want to avoid contact with everyone, because I am ashamed of the fact that I get these constant moods and thoughts and it's not always that easy to control, it's as if I am a passenger and someone else is driving in my mind. My question is, why do people stick with people that has bipolar or any mental illness? Why do people say they love me but that I am holding them back and ruining their lives due to me being mentally ill? Why do people say I belong in a mental institute whenever I explode because of something minor they said, why do these kinds of people stay when they make it clear that they are drained and fed up, that they can never be themselves due to me being in the same room and due to me being too sensitive, that I am not pleasant to be around with and that I make life a living hell? I made a lot of stupid mistakes and choices in my life which led me to go completely bonkers, yes I do blame myself, I do make things difficult and stuff can get pretty rough, but all I honestly want is that whenever I'm in a mood, that people will leave me alone or just ask "are you ok?" I'll talk if I want to, and won't if I don't want to talk. But whenever I hear "oh here we go again" "what's your problem" "you're always like this" "I cannot do this anymore" "I deserve better." That really gets the best of me, and then I snap, and then it's endless fights, day and night. Don't get me wrong, I am very difficult to understand and I am in general not a very great person to be with, I still don't have all my ducks in a row, I am not very successful nor talented, I stopped taking care of myself, because I see no point in it anymore, and I am afraid people might call me vain, which I was, 4 years ago. I am afraid of people. But why do people say they love me when they are clearly done and fed up with me? Why do people stay in a relationship if they made it clear that they don't care what I do or what I feel because it's just seeking attention? I just feel like I should keep on saying sorry, hide my head and not open my mouth, I really do want to get out and away from my mental health, I am ashamed of it, and yes, I do want to be happy and live life to the fullest, but I just don't know what to be or who I should be in order to fit in, I am not as smart and talented as the people that I know, my heart isn't warm, in fact it's stone cold, I am busy rebuilding a wall around myself again, which is my own fault, but I'm trying to keep certain people away from my personal life as well. I have caused severe emotional damage to many people, yet they still stick. Why though? They only damage themselves more and more and then I still hear how difficult their lives are because of me, that everything I do is fake and done with hidden agendas. I am trying to become myself again before everything went haywire 12 years ago, I just don't understand why people would stay even though they are drained, aren't they at fault as well then? I am tired, I am fed up, and I despise myself for everything I have ever done. I really don't feel sorry for myself, need no sympathy, I just don't understand anymore. I really just want to run away and avoid contact at all cost. I know running away won't resolve anything and won't make up for the fights and damage, but I think people will start enjoying their lives again. I can only say sorry so many times, proving I am sorry through actions won't make a difference to most as it's too late. I am just lost.