Besides all the other wonderful suggestions from the PPs, I just wanted to let you know that there is nothing wrong with turning to medication to treat depression if needed. Obviously you are willing to get treatment if it is your thyroid, and mental health is no different; sometimes you just need that boost.
Last year I ended up with some serious anxiety/depression and ended up taking meds. They greatly improved my life, and while I'm naturally on the lazier side, I was able to get out of the house with my kids once I started taking it. It really came in handy when i went through some issues at work that would've preciously sent me into a major panic attack. Now, almost a year later, I'm slowly weaning off of it.
So, please see your doctor and get a full physical and mental health work up. You are worth it.
Amanda - happily married wife to N
and mother to B