I'm agreeing with these ladies, if you look like a woman (feminine features, breast, and female clothes) then going into the men's room is just asking for some perv to take advantage and you mentioned you haven't had bottoms done yet would send some into an outrage. If they are truely your freinds I'm sure they wouldn't want you beaten to death for using the bathroom so I don't see why they are raising such a fuss.
If you want to still keep a middle ground though I'd suggested looking for the handicap stall. Its a single person stall used by the disabled, or special needs people, or those whom feel totally uncomfortable with using the main public restrooms like I do. Most place have one next to the main bathrooms.