Jacqui, my son used to go through the same thing when he was a child. Thinking about infinity literally freaked him out.

It's all so BIG, it really doesn't bear thinking about most of the time, and isn't much use in any practical sense. I'd rather just enjoy myself while I'm here. Anything that happens after that - well that's a bonus. I particularly liked what Spaw said.

Personally, I think this point of view is as good as any:

Hang the sense of it and keep yourself occupied. (Slartibartfast in "The Hitchhikers Guide to the Galaxy")