I think your sister is right, eternallife - believe me I understand the need to 'know' - but even if you were to find out, so what?
You'd not feel any better, and the bottom line is whatever you did, it's done - and can't be undone.
I don't mean to sound harsh - I just know how utterly futile it is to worry about what might have happened - or what might happen to your reputation.
Do yourself a big favour - stop looking backwards - put all your energy into today, not yesterday.
I was obsessed with knowing - for me the obsession was tied into my need to control things...and if left unchecked it usually led back to the biggest control mechanism of all - the bottle.
The one surefire way to make real amends is to make sure you never have to apologise for drunken actions again...and there's only one certain way to do that.
The good thing is? People
do forget - especially if you change your life and show them you're committed to positive change.
Don't worry about loneliness - changing your life means changes - but none of us would still be doing this if the changes were negative
Your main focus needs to be stop drinking.
The rest has a nifty way of falling into place after that
D