Both you and your wife are biblically inclined? I wouldn't give this advice to someone who isn't. Didn't Paul tell women to obey their husbands and men to love your wives? You have some authority here and you can use it to help her.
My guess is that she NEVER excercises and therefore doesn't have any energy. Although being in shape is not an aphrodisiac - a sedentary lifestyle can kill desire.
I suggest you walk with her everyday just to get her blood moving. Make it a priority. Take it easy. Use your authority to get her moving if necessary. While walking with her you can talk with her and find out what's going through her mind especially feelings. Walk the extra mile with her. Be her friend.
When you start to hurt remember to love. Jesus loved even when dealing with people with small minds and evil agendas. Your wife isn't even nasty. She's just ill. I've found this attitude contibutes to my own sanity. Jesus will look after your heart when you ask Him. Ask Him. I did and found out why He's often call the Comforter.
After a few weeks she'll likely be feeling better about herself and perhaps will have lost a few pounds. Perhaps then you can let her know you still find her attractive and want to be close and share each other in love. That this love is important to you and you'd really like her to try again. She just my open up.
Remember in the mean time to take as good care of yourself as you can. Relieve physical frustration whenever you need to. Be sure to interact with your friends and have fun once in a while. Pray deep and often and ask for healing for you and separately for your wife - then for both.
