"Sometimes I think that when you live together for a very lon..." — Fredrik Backman quote meaning

Sometimes I think that when you live together for a very long time, and have children together, life is a bit like climbing trees. Up and down, up and down, you try to cope with everything, be good, you climb and climb and climb, and you hardly ever see each other along the way. You don't notice that when you're young, but everything changes when you have children, and sometimes it feels like you hardly ever see the person you mar-ried anymore. You're parents and teammates, first and foremost, well, and being married slips down the list of priorities. But you you keep climbing trees, and see each other along the way. I always thought that was just the way it is, life, the way it has to be. We just had to get through everything, I thought. And I kept telling myself that the important thing was that we kept climbing the same tree. Because then I thought that sooner or later. and this sounds so pretentious... but I thought that sooner or later we'd end up on the same branch. And then we could sit there holding hands and look-ing at the view. That's what I thought we'd be doing when we got old. But time goes quicker than you think.