My gut feeling says they may very well be. But I feel it could also just be the media being bloodthirsty towards celebrity drama skewing our perception of it.
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.
1. divorce rates have been rising for decades.
2. 60 years is a very long time, and that means Dolly would have had to marry around 18-20. Marrying that young these days for my generation very much is an anomaly, and people are putting off marriage more and more these days.
3. Celebrity culture in particular has a much more tumultuous relationship. In a number of cases, marriage may simply be another influential tool to manage fame and wealth rather than an act of love and caring.