What do you do if your dad doesn't spend time with you?

You can't force him to spend time with you, unfortunately, and there may be other factors involved... he may have to work long hours with little downtime, or he may have hard feelings from the past, or disappointments with himself or his career, that make him want to avoid family. (Do not, I repeat, do NOT blame yourself for this.) When you do see him, make it clear that you want your dad in your life, and want to see him more often. Maybe you can travel to him, or stay with him more? Don't forget to consider his feelings in the matter... and of course, be on your best behavior, whether he's around or not.