wow, that's a lot of stuff.
would 'try to think more positively' be about the worst thing I could say right now? I'm assuming the answer to that will be yes, but knocking yourself down before you've even started really isn't going to help.
as always, I'd say take it one day at a time. try to find something in each day that you're happy with; a nice lunch, or finding something you like in a charity shop, doing a bit of work, having a nice phone call with your mum, whatever.