Arrgh!!! (Top game woes)

We always start on the knees in class and I won't fight for top for very long -- I'll just sit to guard and work. And 90% of my training partners fight for top and won't go to guard to start. So for the past 1.5 years I have been working guard and bottom game 90% of the game.

Result? My passing game STINKS! I have trouble passing all but the newest people's guards, and I have this weird mental block where I don't fight sweeps very hard -- I'm so used to playing on the bottom that I just go with it, get swept, and start playing guard/bottom game again.

We are having open mat on Saturday at noon and I'm planning on asking to start in my opponent's guard. I will work to pass and if I pass or get swept, back into my opponent's guard again.

During sparring I am either going to ask to start in my opponent's guard, or going to fight a lot harder for the top position from the knees.

Just wanted to vent a bit. Open to comments and suggestions.

You see that sounds wierd to me. We often start in different positions during open mat. Just seems to be a culture at our place I guess. I've never been anywhere else, so I really have no idea what normal is. I don't think it should be a problem at all.