Is it normal that i want to break up because of this?

Ok so me and my bf have been going steady for almost 7 years now. He's a really great guy - nice, considerate, generous, blah blah blah - however sometimes, when his father is over, he turns into a total dickwad... And the worst part, he doesn't even notice it! Whenever his father is over to visit, they have this really weird way of 'joking' around, but it's really nasty. It's totally disrespectful, mean and retarded; something they always do at home with my bfs mother too, but somehow she's either too stupid to notice or she's so used to it that she doesn't care anymore (though I think she kinda does because she always gets sort of sad... its really awful to be on their house for dinner or something). And I've tried telling my bf that, but he's all 'whaaat? what are you talking about? Please dont be mad, yada yada yada'!

It frustrates me so much, all the way to the point that I'm thinking of breaking up with him! I absolutely hate it how he doesn't defend me against his socially challenged father! And how he even resorts to making fun of me or the way I see things - something he never does when we're alone (really sometimes when his friends are over though...)

Okay, end of rant... I feel better already... Except today he was a total **** again and I want to dump him. Thanks for reading.