Is the weight you want to lose something that was recently packed on? (Over just the last year or two)
What is your current blood work? All the normal female stuff and testosterone
Are you menopausal or perry menopausal?
Current libido good or do you lack interest?
Basic energy levels good or are they down?
It is not uncommon for women starting in the 40's and 50's to need hormone support such as an estrogen cream or something and your blood work would be the best way to figuring that out. If those hormones are off they can cause weight gain. Additionally, what most doctors fail to look at is a woman's testosterone. If you have total counts lower than 20 ng/dl you could be also suffering from low testosterone. Yes they say the normal range on the test paper is 2-45 ng/dl, but research has shown a negative affect for women when it drops below 15 ng/dl in most studies, but some even say 20 ng/dl is also too low. Testosterone therapy for women is extremely tricky. Most of the time you will be given a cream that really does not help and it is messy. I have found that by subcutaneous weekly injections of 5-10mg Testosterone Cypionate will take a womans testosterone up to about 50-75 ng/dl which is classified as the upper acceptable limit for women. If going this route you may want to consider only injecting every 10 days or so. Doing this from my experience brought my wife's testosterone into a nice normal level. Also her energy levels and Libido are now through the roof.
Now as a word of caution I am not a doctor and neither is my wife. We have been doing what we consider to be a very conservative experiment with this, but I can't say it will work the same for all women and I still can't say it is perfectly safe or free from risks. Also I don't have long term data for you. Wife has only done this for 3 months now and has to go off 2 weeks before she gets her breast lift. Also my wife is 52 years old. This is why I can not stress enough to get blood work at each stage of testing as that is the best precursor to seeing if you could be in for a problem.