I read your post, OP, and really felt for you.
I'm trying so hard to be a positive role model for my daughters but I just cringe whenever I see myself.
I'll be honest, I feel the same sometimes. My kids are so beautiful, I look like a shrivelled up old turnip in pictures next to them. But they love me. They love my wrinkly face, my saggy belly, my uninspiring middle aged self.
Everyone, without exception, has aspects of themself that are beautiful. Not everyone looks like whoever the latest celeb influencer is, of course. Not everyone has the face and figure that matches what is considered 'beautiful' at this moment in time, in this culture. But every person has something about them. A shade of their hair, a tilt in their shoulders, the look in their eyes, a stately nose, voluptuous curves, pink cheeks, cute crooked teeth, a sideways smile. There is always, always a quality in a person that is beautiful and wonderful. You'll have seen it in people you love. If you look closely you can see it in anyone. You have this too. I promise you.
You seem anxious to win the approval of others. That's understandable, but when will you decide to take charge of your life? I bet if you list five ways, right now, that you are a positive role model for your daughters, you can start to come up with some better ways of seeing this. You deserve to feel good about yourself, OP, you don't need to spend so much time putting yourself down.
I would like to suggest a chirpy self help book, that I loved: 'Finding your North Star' by Martha Beck. It's about working out what you want to do with your life, but I found it wonderful for reframing things in more positive things. And it's funny.
All the best.