How do I ask my wife to go to the gym?

First of all, KUDOS for caring about your wife' emotions and health. You are a good husband for that. Second, I understand how you want your wife to take care of herself and lose the weight, too. As an overweight wife, I can say that the last thing that we want to be is unattractive or "uny." It is hard on our emotions to know that we are overweight, especially when it is shoved in our face all day long with magazines, television, pamphlets..etc. The best way to approach her is just ask her...Honey, what can I do to support you with this? Let her know that you love her as she is. Tell her that you are there to help her not nag her. You can not tell her what she needs from you, only she can tell you what she needs from you... Maybe she just needs to take little baby steps because from experience, doing just a little bit to start is more motivating then thinking it is all or nothing because then it seems like too much work and she will not want to do it at all. Any, little steps that you see her make, acknowledge it, appreciate the fact that she wants to be healthy and then let it go. Also, maybe she is mentally trying to grasp this decision and life change, because that is what it is, not a diet. Continue to look for her best interest and you should be fine. Good luck!