Hi JJ and welcome!
I'm 57....and a half. Will be 58 in June. I had 60 lbs. to lose...well, 50 to be my normal weight but 60 to be my dream weight. I'm within 2-3 lbs. of normal and about 8-9 lbs. of goal/dream weight.
AND I started the diet to be at goal by my son's wedding in NYC this coming August.
I started last spring....so you could very possibly do this by May. I can't wait to go and find a sexy outfit for the wedding. Well, not TOO sexy....have to maintain dignity as mother of the groom, of course.
By GI diet, I'm assuming you mean low glycemic index diet, right? I've used Atkins, which I love. Are you familiar with that diet? Low carbing? Atkins would probably fall into the category of low-GI diets....but is much more militant, I'm guessing....as most, if not all, of the foods are probably the lowest there are on the low-glycemic index.
And yes, these types of diets do really control appetite and cravings, etc., don't they? That's one of the things I love about Atkins. Appetite control, increased energy and fantastic results.
I will be cheering for you to reach goal by May.
deena