I am so glad there is a part of you that does want to live - you need to hang onto that part! It's very important and it's going to help get you through all this.
That being said, you don't have to be diagnosed with depression or a similar mental health condition to be upset and to need help. It sounds to me like you geniunely need support to. We all need it in different ways and in different amounts, but there's no reason why your situation shouldn't matter as much as everyone else's. We all do "stupid things," but that doesn't make us unworthy of help.
I really don't think you should feel you're a terrible person for growing apart from your family and friends either. Actually, that's a classic symptom of depression, whether you have it or not. It's not like you are purposely planning to grow apart from them to hurt them, it just happens and it's often related to mood and those strong feelings to isolate oneself that often accompany depression.
I really don't want you to die because I understand you're pain and I know that it
does get better. Yes, I know life isn't perfect, but there are still so many good aspects of it and you will never get to see them if you aren't here. Who knows what wonderful places you may see/what wonderful people you may meet in the future? Only you can find that out if you stay here with us. And I know it may seem hard for you to believe right now, but I promise you that your family and friends would be devastated if something happened to you. If it's hard for them that you've sort of grown apart, it will only be 100x worse if you're no longer here.
Please reconsider what you've been thinking. I see a lot of potential ahead for you, because it sounds like you do have some hope. Please hang onto that hope, you are worth it and you deserve to see the ways in which your life can improve.
Take care