Lightthatnevergoesout · Today 22:21
Just to say that I have no intention of fixing their relationship I have not got time or strength for that. I only start normal conversations because otherwise my father in law sits and looks in his phone and my husband is listening to his music in headphones.
I got 2 small kids and yes they enjoy the company of their grandpa as they haven't got that from any other grandparent in their life.
It's lovely for them to spend time with grandpa, you sound like a very loving DiL. But it's time for you to adjust things to suit yourself.
When my autistic nephew comes to stay, he gets a little anxious about his changed routine and wants to spend every minute with me / us. So what I do now is every evening we discuss the plans for the following day, and then he relaxes. Plans might be - 'you make your breakfast when you're ready and we'll see you at 10am for our trip to the shops', or maybe 'DH is cooking breakfast so you lay the table and be ready for 9am breakfast' etc. This works for all of us as he knows what he's doing and is quite happy to spend time on his own precisely because he knows when he will be seeing me or going out.
Would this work for your FiL? After dinner - 'OK night night dad, we're having an early night tonight and a lie in tomorrow as we discussed, so off you go to the flat now and we'll all pop over and collect you at the flat tomorrow at 10 for our outing. Here's your coat'.
And keep doing that. Don't answer if he rings the doorbell early, just message him and say we'll see you at 10am, as we arranged, remember, ' and stick to it. He'll soon get the idea.
As for DH, leave him and FiL to their phones and headphones, not your job to provide full-time engagement. Go off and see your girlfriends for a couple of hours, and when you come back, tell FiL goodnight and you'll see him tomorrow, then go upstairs and let his son deal with him.
The knocking on the shower door needs to stop instantly. 'Go away I'm in the shower.' Then refuse to answer further. When you're out and dressed, speak to him immediately about it - 'FiL, I'm really surprised you'd try to interrupt me in the shower, please do not do that again or I will be very upset with you and you know I don't want that but you will leave me no choice. So we are agreed on this - you will not try to get my attention when I am in the bathroom or my bedroom.'
It's going to have to be you to make the changes, obviously, so just do it in a bright and breezy way but do it firmly. 'We love seeing you but we're shattered after a busy year so we're having an early night - see you in the morning at specific o'clock' hand him his coat and hold the door open. With luck DH will follow your lead, but at any rate, all the social stuff won't fall to you any more. Good luck OP..