Feeling sad

The title says it all, I haven't felt this down in awhile. And I don't even have a reason for it. (However my period may be nearby). But I've never felt so ashamed to look at myself in the mirror... I am 5'4 and weigh 165 and I know I have a lot of muscle in my legs and a big butt but this isn't the body I want. I used to be so confident. I find myself closing out friends and family just because of being ashamed of myself. I don't know how to pull myself out. I'm trying to diet and it's so difficult since I've been a picky eater since I can remember. Anyone have any advice? Or any positive comment at all? Feeling so lost 😢