I think that for myself, long ago, I put myself in a place, mentally , that wearing a bra is a benefit to me. I told myself that feeling comfortable physically means that I may end up feeling uncomfortable mentally . Then I finally realized that my breasts and having to wear a bra was about me and I am the only person it truly effects. That's when I because mentally comfortable with wearing a bra . I can say that I am completely comfortable with wearing a bra, bra shopping and fittings and even breast exams.
Once you realize that wearing a bra is something that you don't have to do but should, it becomes a lot easier. Even at the beach, I can't go topless but I still want to enjoy the sun and surf. I have to cover up but I don't have to wear a bikini top, I wear a tankini with a built in bra cups for support and coverage . It works and looks like a tank top and I feel comfortable both physically and mentally.