I think how much it's worth it is due to how much one puts into it... I mean positive work... not work that is a detriment to others. Work that makes lives better and that is giving and accepting and nourishing. That means a lot of negotiating and being on top of emotions and what is going on for ourselves... but that is what makes it worth it. knowing how to do that.
If my poly relationships ended and I went back to monogamy, then what would be worth it is how much I have learned about myself, other humans and what capacity I am able to love. That is what makes it worth it. I would use what I know to better the world, be an activist in someway for change towards a healthier planet.. of course I can do that anyway.. so it's all good.