I hope your mood improves soon Holly. You went through a lot in a short time. Now, with the change of season, it could all be having an impact. I think lots of people are going through various things because of the shorter days.
I recently had to have my AD changed and hope it helps me. I have gone through bad mood periods myself.
One thing I've heard to lift your mood is to look in the mirror often and smile as big as you can. And laugh out loud as often as you can. This raises your endorphins naturally and can help especially when the days get shorter.
Keep us posted on how you're doing.