No, generally speaking everyone is, else you starve as an infant.

Maybe this is late night and I need to get some sleep, but you seemed to solve a big mystery for me. Almost all of my girlfriends either freely admire another woman's breast/body or showed a great deal of jealousy. I felt they were a bit bisexual but this makes a lot more sense.

Preference seems unrelated to respect. As a ~straight male I prefer female breasts but I can still respect a chiseled male chest.