Welcome back kelly. The best thing I can tell you to do is try not to have regrets. It was'nt your fault why you did'nt get to takl to your dad. Have you ever asked your mom why was she like that ith your dad? Alot of things happen when two people divorce that the children don't often see.
Mabye if you talk to her and let her know how you feel you can get some answers and you'll feel a little relief.