THanks for the responses, guys. I have to say, I very much look forward to them to see your thoughts on the situation and suggestions.

I know I can't "make" him happy, and I don't think that's exactly what I'm looking for. I think I just need to come to terms with just being there for him as he go through this difficult time. When I am feeling low, he usually tells me that everyone has their down days, and he just listens and is supportive. I think this is something I need to learn how to do better than I currently do. That comes with time and practice, though...right?

So, he also is the type that needs to have his own space sometimes when he's feeling down. It's the total opposite from when he's feeling great. usually when he's in a good mood he cant get enough of me. It's just such an extreme change, I'm just not sure how to adjust. I guess it's a learning process.