We have all our relationship / marriage except for the first two years (and then we were only together during uni terms) - 24 years .
We both had small kids (he had custody of his DD) when we met , but worked it almost like 'two families' during the week for a long time,.DH lived/s in the house we own in another town as his Dd went to school there and wanted to also be near her mum and cousins . I didnt want to move from the seaside city I lived in and had a good job there plus my own house . ( this was also good for us as a family at weekends , as the kids loved being near the sea )
You do have to be independent and also really trust each other in th e relationship (but also really like doing the same stuff when you are together -neither of us had hobbies that took us out of the house at weekends) .. I have never worried that he might be with someone else not he, I.
Its worked and as weve both worked f/t all along Its also worked financially as we now have two homes paid for .
It also probably helped that the DCs went to their other parents every other weekend when they were young. but weekends were always family time or 'our' time..
We have DGCs now! and a good relationship with both our grown up kids..
He is just about to retire ( and hopefully me soon) .. heck, We are going to have to live together!! 