51 not leaving wife.

I'm going out with a man 51 with two teenage boys 13 and 17. As you know Xmas and New Year is the time we all reflect and see where things are in life. But I'm 37 and long to move out from my family's home I've got 1 child 5, two nearly 3 and a 6 month (she's the 51 year old's). Now I asked him if we are going to ever live together today as we have 6 kiddos together and my 4 are living in two bedrooms and a kitchen at my folks place. The only thing is he's just not separating from the Mrs even though she cheated she still cooks dinner and takes care of the kids. But what about my 4 and my baby. I put the hard yards today as I can't live in 2 bedrooms (the two under 3 share with me plus bubs in a crib and my oldest 5 year old has his room.) We have a housing issue as things are so expensive and there just aren't houses and I can't work as I've had a baby recently and my 5 year old is special needs.

I've run it by my sis and she said go closer to where my eldest will get his school in 2025 and start seeing the community there to get to know the ppl.

He hasn't replied to this text I sent about us becoming a 6 and leaving that wife. He said he's staying his first son was septic born then nearly died and he can't read or something so he's special needs and he's said he will lose everything and have to start again..

When I ask about her it's just (I don't know what she's doing) . But don't I and the kids deserve to know he's been with me nearly 2 years?

Do I single mum it yet again and just let it go or do I wait and see what potential we have?