I broke up with my boyfriend of a year today, but his parents bought me a bunch of christmas gifts...?

First of all I really hope you were not texting while driving, please for your own safety don't do that. I had to tell you that. On to the question. Be truthful, tell his family what happened and how you feel, you may be surprised how understanding they are. To be fair Christmas is a week away and I bet they bought you all these gifts a while ago. If you feel funny taking them than tell them that. Did you get them anything and do you plan on giving it to them? Also, has this happened before where you two broke up than ended up back together again? If this is the case this could also be what his parents are thinking and it could happen.