I Am Post Treatment For Stage 3 Rectal Ca, Radiation,chemo,surgery,and

I am post treatment for stage 3 rectal ca, radiation,chemo,surgery,and more chemo. Have a permanent colostomy. Now finding that my vagina is about the size of my little finger. Was radiation the cause? Before I started radiation, I clearly asked rad oncologist if it would cause damage to other body parts. His answer was no and now this. Any hope I can ever have intercourse again.