Bit of backstory.
Ds (22) moved back home last month after a 3 year relationship ended.
His ex didn't like us so they had no contact with us until the relationship ended and he moved back home, we've had no explanation other than "oh that was her, she didn't like anyone."
Anyway now he's home we feel like we're walking on egg shells, It's like having a teenager back in the house, he plays loud music and when asked to turn it down, we have to ask several times and then we get huffing and puffing.
He doesn't have any chores to do but finds it too much to put his plate in the dishwasher after eating the meal I've cooked him.
I put clean sheets outside his door on Saturday morning and they are still there, he steps over them every day.
I try and make light conversations but all I get is one word answers eg Me: did you do anything nice today? Ds: yeah.
Last night was a new low, he went out and came back visibly drunk after having driven home.
I have a breathalyser in the motorhome from when we went to France as it's a legal requirement to carry one there.
He blew 0.12 which bearing in mind he'd been home an hour already was probably higher at the time he got in the car, I think the legal limit is 0.3.
Worse bit is he'd taken a girl for a date so presumably she was also in the car. He could have killed both of them.
I didn't bring him up to be like this, he has a good job and before he left home we were all very close and we were proud of the lovely young man he'd become.
I just don't know what steps to take, he's a grown man, I can't discipline him now and he walks away when we try and speak to him but he's behaving so irresponsible and seems to disregard anything we have to say.
He has younger siblings who look up to him as well. I just don't recognise him anymore.
I don't want to rock the boat in case he goes nc again.