A mommy, wife and friend…a survior of child sexual abuse

What do you do when the mother of the man that molested you does not know what happened?  The relationship with my grandmother was only formed when I was with my molester Alan on the weekends.  I often dread visiting her house because of the over whelming smell of cat urine, not to mention all she can ever seem to do is complain about me or Alan.  I’ve requested on several occasions for her not to talk to me about Alan, only mentioning that he is no longer in my life.  She knows how much of a shit head he is as he hasn’t spoken to her in years.  But what do I do when the need to she her is not there.  I only remember her as a reminder, a link to Alan.  I don’t want to be mean, and I only talk to her because if I don’t I know she will call me and bitch me out.  Why would anyone want that?  She called Friday night and left me a message to call her, it was getting late so I didn’t return the call.  She then called again and left another message Saturday, this time I was busy for several hours.  I forgot she called and then didn’t check my messages until Monday when I had the reminder on my cell I had messages.  She left me a messages with, blah, blah, blah, “if your home, pick up the damn phone!”  Now would this make you just run to the phone to call someone back.  I dreaded calling her.  I always dread calling her.  I don’t like feeling this way, but I always feel obligated to HAVE to call, to HAVE to see her.  Is it ok, just not to call?  My hubby will not allow me or my son to go to her house, because of the urine smell, he is concerned with our health.  I have to agree, the smell is so bad.  I don’t know what to do.