My husband did not come home last night. Is it common behavior in ADHD?

My husband called at 5 pm yesterday that he was just leaving the office. With the highway traffic, I figured he should be home by 7 pm. He did not return my calls or texting ever since and it is already noon next day. I have no clue what he is doing. Last week, he did not come home till 3 am. He said he had a tough day at work, and got so overwhelmed when he called home and listened to my frustrated voice about his late return while the youngest son screaming near the phone. (We have 3 sons. Age 8, 6, 2). 

He has been on emotional roller coaster recently. I lost my job in Nov due to offshore outsourcing and doing full time contract work from home without sitter or any help. He is feeling more financial responsibility with his unstable small business. He was on meds but I don't even know if he is taking regularly as he does not want to talk about it.

Is it common for ADHD husband to take off impulsively to seek solitude and quiet away from his wife and kids?