How do I stop thinking about TTC

I've been TTC for 5 months now and no luck... I think I'm driving myself crazy cause I can't stop thinking about the possibility of being pregnant every time my boyfriend and I are intimate and it only gets worse the closer it gets to the time I'm supposed to get my period every month... I know this has a lot to do with me not conceiving... Do you ladies have any suggestions on how to turn it off and just relax and enjoy? 

Thank you so much! Baby dust to all of you!!!