Thanks for writing! It is always so challenging when medications cause weight gain - unrelated to your eating habits. With bipolar illness, it is very common to have major weight gain with medications. I'm glad to hear you've been compliant with your medications - which is number 1 - and not letting weight gain interfere with this. Now that your mood is stable, there are a number of ways to lose weight and keep it off - although it is difficult. First, seek the advice of a nutritionist who is going to help YOU with the best method to cut calories. Exchanges are confusing for many people, and won't work for you. I'm sorry you were put on a plan that discouraged you. Speak up if the advice you get doesn't seem to be workable for you.
Next, it is VERY do-able to have one meal for both you and your husband - you're not a short order cook! For you, the basics are lean protein, and fruits and vegetables as the primary source of carbohydrates, and limited amounts of high-fiber whole grains. (Plus eliminate calories in liquids (juices, sodas), except for a glass of skim milk daily). So, dinner for you might be a grilled chicken breast (take off the skin), a cup of broccoli, and a small baked potato (the size of a baseball). You husband could have 2 chicken breasts, or a breast and a thigh, broccoli, and a larger potato. Perhaps also a whole grain rolll, that you can skip. You could have a bowl of strawberries for dessert (with some fat-free cool whip for dipping), and your husband could have some fruit and perhaps a couple of cookies.
I'd suggest getting some on-line help, which is easy and convenient, and even a trial membership with www.weightwatchers.com could be great to get you started with eating and behavioral information, as well as some exercise support.
You might also pick up a copy of The South Beach Diet, which is easy to follow, has food lists, and serving sizes, but not specific calorie counting. Many people do well on this plan. Also, check with your primary care doctor, as a medical center near you might have a structured, comprehensive program for you to attend. Also, call your health insurer, as many plans have covered weight management services.
Go to the bookstore or library and check out the weight loss section. Find a book that appeals to you. As long as it is balanced, is not extreme or eliminate food groups, you should be fine. Remember, if a plan sounds to good to be true, it probably is!
Good luck! Let me know how you are doing!