She is a normal girl with no other mental illnesses
OP, just needs to man up and go for it.
I understand her being a virgin could end up being an issue, but you guys are young. I think this would be good for her considering its probably hard for her to deal with the fact that shes handicapped and her friends are makin fun of her for being a virgin.
People can be mean so show her that she can still lead a normal life including scoring some cock when she wants it.