I'm really sorry to hear about everything that you've been going through, that's rough, and my heart really goes out to you. When I came out, things went very smoothly, and I was extremely blessed for that reason, so I can't imagine what might have been said to you when you came out or how it's all made you feel, but I can tell you this...
Keep your head up, and stay confident in the way that you feel about yourself. You obviously know what you want out of life, and what you want out of your transition. They're clearly uncomfortable with it, but that doesn't mean that they'll never come around, it might just take a very long time (When I came out, my father bought me girly things for Christmas, the next year, he bought me boxers...out of the man's department, and Old Spice, I've never been so happy, and I was sure that he was starting to understand how important my own transition was to me)
But anyway, the point is, just make sure that they're able to see how happy these changes are making you. It'll reassure them that you really are making the decision and they might be able to get over the 'Oh no, I'm loosing my little girl,' if they see how happy it makes you to become a man.
As for the bathroom situation, I don't have a lot of experience with this. I avoid male bathrooms when I'm not at work, because I know that I don't pass...other than with my co-workers. If you know that you pass, then don't be afraid to walk in there with your head held high...just don't talk or make eye-contact, from what I hear...Men don't socialize like women (Strangers, might I add) do in the bathroom o.O;;
Best of Luck! <3