Hi Jay, I know how you feel.
I've never been the life of the party so you have probably experienced more of a change than I have. But then I've so totally isolated myself and I don't have a wife/children/anyone that you have. It's been close to a a year since I have had lunch at work at noon when everyone else does. I've stopped reading the news so little of the world leaks in. (I haven't watched TV in years but that was a choice not related to what I'm going through now)
Things were so bad I didn't care if I was alive. No I was not suicidal but I just didn't care. I was so fatigued all the time. I was asked by one woman at work I sometimes talk to if my physical activity/exersize helped put me in a better mood. (I bike to/from work 10km each way from spring-fall, 1hr on treadmill/day in winter) I told her that I didn't know, that if I was in a better mood because of the exersize then I better not quit.
But after months of this I have been getting better. Still it is crap but not as low as I was before. A long way from what would be acceptable but I feel more like I am in a tunnel (still no light) but it's not the pit I was in.
I'm sure you will get better and that you just need to ride out this period in your life. Find things that interest you even if they are with or without people.