My husband is mad at me so he’s sleeping in the driveway

My husband and I had an argument last night. He was 100% in the wrong and acted completely out of line, said some vile things to me and was acting totally out of character. He slept on the couch last night after the argument. He went to work this morning and totally ignored me before he left. He obviously left work early today because he’s back home way earlier than normal. Like 5 hours early. He arrived back at our house two hours ago and is just sleeping in the driveway in his car. He hasn’t come inside at all and hasn’t said a word to me. I feel super embarrassed because my neighbor already noticed and texted me to ask if my husband is ok because she saw him in the passenger seat sleeping. I want to leave the house because this is a ridiculous situation but unfortunately we are sharing a car right now until mine is fixed sometime next week so I’m stuck here because he’s SLEEPING IN IT. I know he’s trying to prove a point to me that he thinks I’m the one who should be apologizing but I’m not the one who is wrong here. How would you handle it? Ignore him? What do I tell my neighbor?