Should I get married?

My g/f of 8 years wants to get married, we're going ring shopping and talking about it. However, I've had lots of trouble with this girl over the years. She gets so snotty with me over stupid things. Little things I do annoy her (I'll joke with her and I'll be totally kidding, but she takes me seriously and tells me to leave). She doesn't share the same sense of humor as me, I'm easy going and she's tightly wound. Plus she doesn't seem to have a full grasp on how to do things in the bedroom, no oral? Plus times there is action, it seems to be few and far between. The more I think about it, the more I'm like NO this can't be the rest of my life. I feel like I just let her come in and take over my life, we don't even have anything in common, ok we like same sports team big deal! When I hear about other people's relationships it just seems like this is how it is (especially after marriage), but I don't want to settle for this kind of life. I've tried to break up with her in the past, but she'll stalk me until I give in and come back. What do you guys think?