There is more to a person then looks. What about her qualities and values? Is she easy to talk to? Does she treat you good? You could walk away and meet someone "more attractive" but that doesn't guarantee the grass will be any greener. Also, you need to consider her feelings. She probley already has very low self esteem from gaining weight and you are not helping any. My suggestion would be to give her a compliment here and there. Tell her her hair looks nice or you like her outfit. Possibley by boosting her self esteem it may give her more incentive. You could also tell her you are concerned because obesity puts you at a higher risk for many health problems. Tell her you want her to live a long life with you. No matter what you married her for better or for worse. My guess is that you are no supermodel yourself.

When you go out with her, let her see you looking at other women that are in shape. But don't say anything about the girl you looked at, just let her catch you and take the beating, if she cares, she will try to look like what you were looking at, if not, then she don't care what she looks like for you.

An update to my original post:

I had explained to you that I had every test possible done to figure out my weight gain, etc.

I expressed my frustrations to my boyfriend, stopped going to the gym and made another doctor appointment (he's been very supportive).

I'm not sure what you wife's situation is, but it turns out my vegetarian diet was making me fat... IRONIC huh? (I can tell you more if you are interested)

Two months ago I had to start eating meat (BLECK) and dairy (BLECK AGAIN) and even had to start eating "some" junk food (yuck again) and stopped going to the gym so often, actually I don't go anymore because it was depressing.

Anyway, point of this little story is that in two months with a change in diet, eating things I thought were not good for me and KNEW I didn't like, I have lost 20 pounds.

Her diet may even be the simple answer :-(

Here I was, eating nothing but health food, and getting fat from it. HAH!

Hey I know it is going to sound very wired, and you will probably leaf like I did, but did you try to spice your sex life with some toys, it really sound crazy but I worked for me and my girl, we are practically in marriage, we lived together for 7 years, but in past two years our sex life was gone to having sex ones in a three months, that was so bad period, we are thinking the same, cheating! We did not thrust each other any more, and when we are practically at breaking point, she bought me fleshlight! Can you believe?? I was like that is so stupid! But now I can't wait to come home to her, we barley use it now, but can tell you that the change was exactly what we needed, she said she is going to buy me another one because my birhtday is coming, and I can't wait!