I can't believe some of the comments here and the PC down vote brigade.

My now-ex wife was overweight. I ended up losing attraction to her which led to us splitting up. Being a very active guy, I brought it up multiple times during our relationship because her being in shape was important to me now and for the future with kids. She would take a couple weeks working out and eating well and then jump back into junk food. We were living across the country for a while and she gained even more weight while claiming she was working on losing it. I cooked everything healthy for her that she enjoyed eating once we were together again, yet I would still find Wendy's or Taco Bell wrappers in my trash after I came home from work on an almost daily basis. It was the leading cause of our separation - which I might add was on good terms, we are still friends.

A few times I brought it up I mentioned her mom who has diabetes and is obese. Even though my wife was also definitely overweight, her response was - well I still wear a size X, and I'm still much skinnier than my mom. Most women I've been with are either hyper sensitive or extremely unaware of their weight until it's too late. "She probably knows" is complete bs, especially with how people are being coddled these days.

If you see a future with someone, and something is important to you, bring it up. My wife thought that because I didn't mention it at the very start of our relationship, I didn't mind her figure. For the record, our relationship ended when she was almost 50 lbs heavier than that day. She was adamant that she still looked the same even though she acknowledged the weight gain.

Now, if you're breaking up with someone, you don't owe them a reason to make them feel even worse. If you think you have a future with the person, it is definitely not out of line to show your concerns.

I'm sure this will turn into some variant of "wow stop fat shaming" crap and from how things have looked I'm prepared for the down votes, but ffs life isn't some rosy "no criticizing" zone. People need to grow up.