Definitely get married, the term marital home has a lot of weight and legally being able to access monies you didn't earn, ie his pension which he is building quite nicely whilst you don't have a work pension and an employer contribution.
This comes down to expectations the main ones being finances, access to, what you spend if there is a limit, what you both deem as important to spend on and the other is household and child rearing. On the household and child rearing front as far as Dh was concerned when he came home we were a team, get everything done that needed to be done and then both be able to sit down. However, we both recognised that sometimes you just need to tap out and have someone else solely responsible.
Dh had a lie in every Saturday and I had one every Sunday. He was a full hands on Dad from day 1 so would never wake me or secretly send the children to wake me, he never shirked his responsibility as a parent.
The biggest killer is the repetitive days and the loneliness and lack of adult conversation. But with podcasts, audio books, radio shows on demand, plus any streaming service for movies, tv shows etc makes it easier to get through the drudgery of folding laundry, again.
Being organised helps, accepting that some days are going to be much harder than others but having said all of the above, it is the best thing we ever did, both Dh and I still talk about it. I am a long term sahm, due to ill health no one would employ me but being at home has meant I was able to manage my medical condition and actually improve it. My youngest child is now 18 and about to go off to uni. Absolutely no regrets but then I had my best friend (Dh) to do it all with.