Am I too demanding?

I've been married for 3 years. My wife always used to look after herself. During the last 1 and a half years she added a few inches around her waist and bum. She also got cellulite on her upper arm, legs - lower leg as well.

I've tried everything for her to get rid of it. I bought her a scale; I bought her one of those machines which shakes the extra pounds off and she joint a gym, but never goes to exercise.

I'm really so frustrated. I'm looking after my body. I do sport and eat correct. It’s just as if she doesn't care. And we fight about it so seldom. I feel to get a divorce, because of something so stupid. I even said that I will go to the gym with her. We earn enough to buy products to get rid of her cellulite, but she is just not getting so far.

I can't help feeling that she can look better, that she can put in more effort. I'm a good husband, I help her with allot of things in and around the house e.g. cooking and washing dishes. She doesn’t ask for it, I just do it. The one thing I asks her is to look after her body and she just refuses. She always makes promises, but don't deliver.

Any advice or suggestions.

Thanks

Updates
+1 y
I just would like to set the record straight. I didn't buy the scale or the machine out of my own. She asked for it as birthday presents, and said that it will help to motivate her. She is 33 years old, we have no kids, she is healthy and pretty looking.
Am I too demanding?
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