Friends in school

I want to start out by saying I don't want this to seem like a little kid making a huge thing out of nothing but it has been affecting me for a while now. I have a group of 3 "friends" and we all hang out etc. but I have never felt close to them. Furthermore, one of them is a homophobe and makes offensive comments without knowledge that I am bisexual along with constant negative comments on my newly red hair. Both her and another member of our group never consider my feelings or genuinely ask if I'm okay and spend around 97% of the time bitching and complaining about insignificant things without trying to sort out their problems. They also exclude me from a lot of conversations and activities. I have explained how I feel about all the subjects mentioned. The last one of the group was originally a pity friend as she is the "outcast" of my class; I felt so awful that I decided to start again and become true friends with her and now she feels like the only friend I have. However, I do have a very close friend who I text every day but he lives quite far away and neither of us can drive so it's hard to keep that friendship strong. We have all been together for around 3 years now and I have frankly become fed up with them. I have only kept being friends with them because I did not want to be alone again. I already spent 2 years with no one to talk to, or just be a friend, and having a feeling of no purpose and that God had abandoned me (no longer a problem). I feel like I should end the friendships but it would make everything awkward and tense around us. Gladly, I am moving school soon but I feel like a massive burden has been lain upon me and it won't be lifted until I tell them the truth. I guess I just want advice on what to do as friendships are important in life and I don't feel as though I have that.

Is there any point to confessing and thereby hurting them as well as greatly inconveniencing yourself when you're going to be moving school soon anyway? On all fronts, what would it achieve? Or is hurting them (back) before that window of opportunity closes, the underlying point?