Sounds like Major Depression to me ... Sorry you are experiencing that. I know from experience it is a living hell ~
by reaching out to talk to ppl however is a good choice!
Eliminating ppl out of your life at this time that bother you - may not be such a bad thing - if they make you feel bad about yourself. You sound like a worthwhile person to get to know however. You need healthy support for sure .. someone you can talk to and feel safe and comfortable.
Dissociation form ppl is a little different from say ..losing time .. and not realizing it etc..
Reach out - maybe find a therapist to sort out your feelings and separate wht issues belong to you and which ones come from other people. Begin to get to realize your worth and value .. sometimes you just have to build yourself up to that point..but is possible.
If we coud dissappear .. thinking.... would it bring happiness? Find Joy in the little things in life .. they may be small but there is beauty in just about everything you see around you. including yourself you were born a Miracle - you are STILL a Miracle from God
There are ppl who care about you ... especially your mom!
If one person can value the way she does .. Life is worth living .. my guess is you have many who care for you - try one person at a time .. till you build yourself up enough to take on another. Baby steps. . one at a time. .one foot in front of the other..One moment at a time will bring you peace ..more and more as time goes by.

Hope to talk to you again sometime -