I suppose working at a relationship means that you have to be prepared that at some point compromises will have to be made and not always by the same person. It means recognising that sometimes things can go a bit staleand that you are both responsible for recognising it when it happens and for changing things in order to improve and move forward.
I think most relationships experience times when you feel as though you are in a rut. Sometimes it happens because one or both of you are just plain tired ( especially when you have young children), sometimes health issues play a part and yes, sometimes it is down to a certain type of boredom that can set in just because you sort of feel almost too comfortable with each other and sto making an effore to keep things exciting and 'new'.
It is harder to say what constitutes a marriage or relationship worth working at. When we were in a similar situation, for both of us it was a case of imagine life as it is for the next 20 years? Now imagine life without each other for the next 20 years. We each felt that we didn't want our life in 20 years time to be like it was at that time, but equally, neither of us wanted to even begin to imagine life without the other one. It was that that convinced us we really did want to make things better and dig our way out of the rut we had created for ourselves. We loved each other and despite the boredom that had set in, we never stopped loving each other. And I suppose ultimately, it is love that made it worth working at our marriage.
As for what we did, well, we began to rebuild our sex life, which had become non-existant . We now make plenty of time for that, easier for us maybe because our kids are teenagers so are often out. We began to make a conscious effort to do things together, maybe going out for a walk. We hold hands. We make each other cups of tea, we share a joke together,we make sure there is lots of physical contact, cuddles, a snatched kiss when I am cooking dinner. He helps with lots of housework ( I am talking about a 40% share)because I also work. we remember to say @ I love you' instead of assuming the other one knows it! It's just lots and lots of little things that over the course of a day, or a week, show that we love and appreciate each other. It is not the grand gestures, we can't afford those!
We are not perfect. But then, nobody is. And no relationship is perfect. But I would say ours is good and very strong, as are many , many relationships of folk on here. It is just that by the very nature of this board in particular, you will read about more of the other kind of relationship.
Sorry, I don't think I have been much help, but maybe there is something here that might be of use to you.
Good Luck