How to deal with unwelcome family visits?

Hubby's birthmom and half-brother (who is married and has 1 child) are complete moochers. Always looking for freebies when traveling (aka, wanting to stay for long periods of time but never go anywhere...expect to be entertained and fed for free) and every year they stress me out. I haven't had a fun holiday for years. We have two children and I want to make new family traditions but his 'mom' is always lurking around when I just want to spend time alone with our kids. I've told hubby (and he knows) that I hate how they try to take advantage of him. Luckily we have a small house so we don't have room for anyone to stay for long. It's just the fact that they expect everyone to stop their lives to accomodate them. How do you deal with the stress???