I don't understand how you have got in this position in this day and age?
You are the role model of 2 young females so how you are treated and expect to be treated will be very influential.
To put it bluntly, there is always, or should be, give and take transactionally if there is no marriage contract which basically is a financial as well as a security blanket for the woman if she does the 'unpaid' part of a domestic set up.
Do you do his laundry for free? His cooking for free? Home maintenance for free? Bulk of childcare? Gardening?
These all add up and no woman should 'volunteer' these services for free if there is nothing financial/ life security for herself and her children in kind offered from their partner.
You never should have allowed him to use you and use your services for free like this as it has just enabled him to abuse your love for him, it's all take take take from him. He gets all the benefits of a cushy and comfortable married life without having to provide you and your DC any of the financial cost to him.
He knows exactly what he is doing and you have been happy to be the mug.
No man would ever put himself in such a vulnerable situation for 'love' where they ' volunteer' all their services for free with no financial benefit and security in return.
Luckily you have the chance to open your eyes to this one sided, horrifically financially and emotionally abusive scam of a relationship that just benefits him and you have the chance to role model to your girls that men cannot behave like that and call it love.
This is no demonstration of a loving domestic relationship and family set up and as such is a toxic environment to being up your girls.