I have been searching for this manga I read a while ago about a middle-aged make-up artist who reverts to her old high school self while remembering her first love that didn't work out for whatever reason. I don't remember correctly if she was bullied because she was really shy or if the first love was dead, but I remember her consulting her pregnant engaged friend before she went back into the past due to fact she was still a virgin at 32.
This is Seishun Cinderella.
High school girl Shion decides to confess to the boy she likes. However, even before she can say "I like you", she receives her answer: "If you want to confess, at least do something about your appearance". Ten years later, Shion works and has much more style, but still can't manage to have a normal relationship with a man. Ever since she got that answer, time has stopped for her. By pure chance she finds a photo from that time and, as she tears it up, she finds herself catapulted back to the same time as the photo. The modest high school girl from ten years ago has returned, but now she knows how to put on makeup and dress fashionably. And so, Shion has a second chance to live her high school life and erase her regrets.
The synopsis is a perfect match for the question. The main character confesses to a boy she likes, but it turned down due to her plain appearance. She ends up working at a department store doing makeup for other people and is significantly more fashionable at this point. She still doesn't have a boyfriend, and her pregnant friend suggests she find someone at a mixer before she's too busy with her pregnancy and child to help her out anymore.
By chance sees a photograph of her old self, a female friend, and the boy she had a crush on. She tears it up and goes back in time to when the photo was taken.
Found by searching mangaupdates for the tags
Time Rewind and