Low self esteem

So my grandpa is a very rude guy but most of the time I put up with him cause we live with him and idk why but he seems to have a problem with bigger ladies but my family has a lot of them and he doesn't hold back on his rude comments and two weeks ago we were sitting down eating and this girl in like a sumo wrestler costume comes on and he points and says hey it's you and at first I wasn't really bothered by it and I just brushed it off but today I barely told my mom about it she's a plus size like me I guess and I told her what she said and she was like well you are fat and when she said that I just wanted to cry and idk it's not like I'm not trying I go to the gym I eat stupid salads every day I'm 17 and I weigh 190 I know that's bad for my age and I'm trying but it's hard when you don't have any fucking support. And yeah I guess I just wanted to be a baby and cry about it to someone.