HELP!!

My boyfriend got into a reckless accident last month. He is not hurt but he has been carless due to not getting his car out of the impound lot til yesterday we went and saw it is totally underivable. I feel he should have checked on this sooner. He assumed he would drive it home yesterday but now he is still carless for a while longer. I understand the frustration. The car he crashed wasn’t even in his name, anyway I have been driving him around 95% of the time to help him out and because I’m his girlfriend but is it okay some days to say no? He says he won’t get mad cuz this isn’t my fault, I basically need to know should there be a balance between helping out and saying no sometimes?