OP firstly ,not a kick at all because I get it , but don't rely on your loved ones to boost you solely , they are flawed human beings themselves and even the best of them will slip. You have to look at your own self esteem and it's got bugger all to do with you not being pretty enough. Love is loving someone and finding them loveable when they look the worst possible.
I actually understand in retrospect. I had never really noticed or cared that exdh never had photos of me. He had them of DC but never me. To be honest I just didn't think of it for years.
Time goes on , marriage fails.
More time elapsed and I get into a relationship with DP.
Who after a while I noticed had kept a random photo of me that had fallen put of a box while we were moving , it's one of me from years ago , well before him. It sat on his bedside table.
Then I noticed a rare one of us I took at dinner had been printed out and put with it.
Then finally I chucked some socks I his overnight bag as he was due off to travel for work and found a copy of our picture in his bag. I asked him and he takes it with him when he travels and puts it in his hotel room and it hit me. I had never noticed with exdh that he never cared about having a picture of me but DP did.
So I understand completely what it means to you. It's not unreasonable for it to hurt a bit. The absence of photos didn't hurt me with exdh but it is a sweet thing with DP.
Having said all of that , your wording about yourself is heartbreaking. You don't have to "look pretty" to be beautiful. It's not about being perfect it's about the person sat there in front of you and just being them. Easier said than done at baby stage but if you can try to remember you are amazing , you just produced an actual human being! Surely that is more beautiful than lipstick or hair curled. For a moment screw what he thinks of you , try and increase what you think of you.