Good for you OP.
I think you realise that you are actually at a critical juncture in your relationship.
He either steps up and behaves like a father and husband in your marriage or most likely this is the beginning of the end.
You will start to detach.
You will get your ducks in a row and you will move on.
However this conversation goes tonight I would strongly recommend that you just pull back in your general accommodation of him and his life.
Without wanting to criticize you at all, perhaps think of just how much you have allowed things to get to a stage that he is such a selfish twat.
These things rarely happen overnight but little by little.
Whilst I would be very, very calm in your meeting.
I would give it to him with both barrel's as to how much he has been taking the piss.
Having it in all written down in black and white means it can't be dismissed and forgotten about.
This is a very serious conversation, that could be a deal breaker for you going forward.
Going softly, softly will only lead to further exploitation of you.
Spell it out very clearly.
He may even need to take some time to look at what's written down and reflect on what you've said.
Give him 24 hours if needs be and then put it completely back on him.
Ask him:
What are you going to do about this?
What are you going to do to fix this?
How are you going to step up?
OP you could spend years on this bullshit.
You might as well know now.
Best of luck to you.