I think money, fame, celebrity status, etc. often creates pressures on the relationship.

Kind of like how it sometimes pushes people into drug addictions. That's a stereotype that we've all heard about since kids, but it wasn't until relatively recently that I thought about it seriously that it occurred to me that a touring celebrity musician's life can be stressful and the drugs can be (or start out as) a pressure valve release. I think that part of it clicked to me when I heard a musician being interviewed about it, I forget which. Maybe it was a Beatle talking about their early amphetamine days.

Re the drug addictions - another thing to note about touring musicians is that there's a lot of downtime. New cities every day, not much to do until your show in the evening. Pretty easy to slip into unhealthy habits.

I had a friend in the mid-90s that was in a mildly successful band. They did a few national tours as opener for bands like The Red Hot Chili Peppers. I met up with him once while he was out on tour. I was thinking he was living his best life, like he was gonna brag about the lifestyle. Just the opposite. He hated touring, said it was very stressful, and that he just wanted to eat a home-cooked meal and sleep in the same bed more than two nights in a row. And yes, he said industry folks were constantly pushing free drugs.