hum that could be a lil tricky o.o id say you either
1.abort
2. tell her family(not good her dad may harm you)
3. get her to tell before its held off too long, waiting several months is another excuse for them to be mad
4. try to get your parents to talk with them as well to calm em down(might make them hate you even more)
5. never bring up abortion as your parents already know shes pregnant