just so you know sedatives can be a depressant. so when you "awoke" you were even more depressed than you already were. i'm glad to hear you're in an anti-depressant now. takes time to kick in, so be patient. my anti-dep. helps me function so much better.
attention seeking behavior-that could be cause you were reaching out for help and didn't feel heard.
pdoc. try to work with him if this is your only option. what do you not like about him?
if you can see a therapist as well it could help you better understand the triggers for your depression. it can help you a lot by giving you coping skills.
as for announcing you were engaged-that is a tricky one.
one option-wait til someone asks about it, then say it wasn't for you and it's no longer planned.
second option-just fess up about it as u see ppl you told. say you were having a difficult time healthwise and mislead them. that you apologize. no need to say more. if asked just say you'd rather not discuss it further.
pusing friends away-i'd go to them and tell them you're sorry about how you were acting. that you were having some life problems and took it out on them. if they are true friends they will accept your apology.
hope this helps you not to worry. you made some bad judgements but it's not the end of the world. good news-you're getting help.