I wrote a reply a while back, but I see it's not here.
Basically I'm in a similar boat. Well, I'm going to say "was", because things are going much better now.
I had a couple of kids, and although I lost the baby weight through cutting calories and exercising, I soon developed my own chronic health problems. My problems turned out to be easily controlled, BUT it took years to figured that out. The doctors had no idea what was wrong with me, and no ideas what I could do.
Eventually I figured it out for myself, but it took a few years. Cutting gluten out of my diet took care of my constant vertigo. (I thought I was having seizures). Going off birth control pills took care of my severe ADD-like symptoms, anxiety, and depression.
Unfortunately, while I had all those problems, I was not able to stick to any kind of weight loss or exercise program for more than about five minutes. I took everything I had not to gain weight more rapidly than I did. I should be happy I only gained 30 pounds.
So, like you, I've got 30 pounds to lose. If you want tips, I think the one that comes to mind is to weigh your food and log it in no matter what. One mistake I've made in the past is that when I knew I'd eaten too much, I didn't want to actually see the numbers, so I just wouldn't log it in. Next thing I knew, I had fallen off the wagon and gained weight.
Starting weight: 157 lbs.-- June 23, 2010
Current weight: 149 lbs.
Mini-goal: 136 lbs.-- November 1, 2010
Target weight: 120 lbs.-- February 21, 2011