There is a really good book: "Women, Weight, and Hormones". I loved this book before my surgery, it has lots of great advice and pointers about our situation with weight and hormones. It has great stuff in it.
On that note, I also consulted with a compounding pharmacist who said while the book is great, the author, and MD is not a proponent of progesterone, and said progesterone IS needed even if you don't have a uterus, to balance estrogen levels and he felt progesterone helps for an even more natural HRT than just plain estrogen.
I am not a professional, but I am following both the book advice, and the advice of my compounder. I am on Vivelle Dot .1 and 3% progesterone cream (and progesterone definately helps ME sleep better!) since 24 hours post op, and I am doing even better than I'd ever even hoped for.
As far as weight, I was 182 pre surg, am now 163...and follow the diet advice in the book. I haven't yet been able to exercise, but cannot wait to see what happens when I do start my walking/jogging. (Yes, I did have a tummy tuck, but two days post op, I had only lost about four pounds).
I have always been in the 148-155 at 5'71/2 (and muscular/trim) range all my life, except for gaining ALOT with each pregnancy (my compounder said certain types of women who gain alot during pregnancy respond well to a well balanced hormone HRT!). I gained like more than 50 lbs with EACH of my four pregnancies. I had always been able to diet and exercise back into a slim size 10, down to under 160 with all four pregnancies. WELL, when I hit 42-43, and perimenopause struck, I ballooned up from 160 in 2000 to 188 in March 2003! The compounding pharmacist and the book BOTH confirmed the increase in my weight is due to the fact my ovaries were beginning to make less estrogen, and a woman's body fat increases to make estrogen to replace that made from the ovaries. I have also notice a striking difference in my carbo cravings. The compounder said that declining estrogen causes changes in your insulin (the hormone that effects sugar uptake to cells) interactions, and that a decline in ovary estrogen will cause you to crave carbohydrates to enable your body to make more fat, and increased fat makes increased estrone (a weak estrogen) - so a hormone inbalance does cause fatness. He said that it isn't the estrogen, but an imbalance of ALL the female hormones is what causes the fat around the tummy of midlife women.
Well, I am now surgically in menopause, replacing my hormones, and I have LOST in about one month, nearly 20 lbs! My libido is getting back to what it was before 42 also...my libido had just nearly disappeared! I was seriously getting upset watching myself "hatch" into some routund middle aged, sexless feeling woman!
Now, I am no doctor, and yes, I am on a pretty tight diet, but a good diet - but I am a believer now that it was what I thought it always was - and that was a hormone imbalance of midlife that caused me to gain all that weight after 42.
This is just my experience, but if you want to know more, the book would be a great place to start. It has worked for me. AND NO I have no income from the book!

I wish I did, as it is a good book for this hormone stuff!