Hi, welcome to our "club".
I am going to play Devil's Advocate here(or Armchair Psychologist) .
You mentioned that you moved from "family" to be nearer to your kids, then gaining weight. It's a big change to go from a familial support system for YOU to being the matriarchial suport system for your kids, even if they are grown , kids tend to add stress and without someone near to support you when you are stressed, you may be feeling the strain without really knowing it, hence the search for "what's wrong".
Since you obviously aren't averse to trying new pills to help with your dilemma, I strongly suggest talking to your physician about DEPRESSION and what you can take to alleviate some of the symptoms of it, the main symptoms of which you have pretty much defined in your initial blog entry above. Major life changes, unexplained/non medically specific weight gain, apathy, sluggishness, exhaustion... on and on and on , sweety, there are really good medications out there for your symptoms and it's not a sin or a shortcoming to have depression.
Next off, as for your diet and how well you eat and your exercise, well, as we get older, our metabolisms slow down. FACT. So we have to keep our bodies guessing as to what we are gonna throw at it next to get the same results we got when we were in our 20s.
Throw in about 2 very quick 5-10 min hardcore cardio sessions every day for a couple of weeks. Check out these free downloadable sessions on utube and try them
http://www.youtube.com/watch?v=_DfuU3TSsFM . Just adding one a day even may be the key to push your metabolism back up into "burn" mode.
Perhaps , now it's going to be more crucial to watch exactly how much you eat. Maybe time to purchase a small food scale and start yourself on an intake charting system like WebMD Food and Fitness Planner or the Fitday.com one. These are essential tools for learning how to eat and exercise for our goals.
Hope this helps some. Wishing you well on you journey and let us know often how you are doing. Blogging here helps because of the support system we can provide.
Kim
Kim SW 243 CW 193.6 GW 135
Many of Life's failures are experienced by people who did not realize how close they were to success when they gave up. --- Thomas Edison