Well, did you tell him.

It sounds like a legit question to me. I'm not sticking up for anyone, but if you've never been fat you obviously don't know what it's like. As the bf stated, he was wondering, which makes him curious. If you're wondering about something, you usually ask about it. Better to be informed than ignorant

Sounds to me that he had an honest question. No need to get butthurt about it. He didn't ask you ''hey babe how do you put up with being such a fat tub of lard all day?'' He even hesitated. Either formulate and answer or say you don't wanna answer.

"How does it feel to be single?"

Leave him.

What an asshat

Should respond, " probably not as bad as having crap sex with a guy whose package barely works" It's mean but it will make him feel like crap too. Then perhaps dump him

What a nice guy...(insert sarcasm). Get rid of that insensitive jerk

He might not actually expect her to have an answer, he might be genuinely curious. For example, I'm a guy and one of my friends did the same thing except he said I wonder what it's like to be a girl. Clearly not a stab at me, but could be twisted around to be that way. Maybe OP's bf has some kind of repressed fetish about getting fat.

Wow, some guts on him. I'm picturing the Insanity Wolf meme. You don't say that to a woman, unless maybe you want a limp and a soprano voice.