Grumpier Old Men

I'm going to get a little personal here. I live in the same town as my grandparents, and they're one of the reasons I decided to stay in the area after college. They helped me out a lot while I was in school, and even let me stay at their house for several days while I nursed my broken toe. I love them dearly, but there's something you must know:

My grandpa is a jackass.

It appears to be a life-long problem. If there is something that he can pick on Grandma for, like leaving a bottle of olive oil on the counter, he'll do it, and then not stop. "You have time to go to Al-Anon and Red Hat Lady parties, but not time to put the cap on a bottle and put it in the cupboard," he says. Then again 5 minutes later. Then again later in the afternoon. Then again when someone new comes to visit. I nearly broke down last night because he was viciously harassing me for not knowing when the last time I changed my oil was. He told me that he was going to have to call my parents and tell on me, a 23 year old adult who can change her own oil. It was the dumbest thing to pick on me for, and he wouldn't quit.

I got off work early that day and came over just to see them. I come over because they're my family and I want to spend time with them, and I'm also really lonely at my empty house. I don't go over there to get my weekly ration of verbal abuse.

Grandma goes to Al-Anon, and that apparently helps her deal with him. I don't have those tools. Last night, I just did not have the ability to handle something so stupid. I just left. I don't want to go over there again, because I know he'll berate me for being so sensitive, and then we'll be back where we started. I'm really the only grandchild who regularly comes to visit. Why does he pick on me? What am I supposed to do or say? How do I love someone who drives me away?