Show business in general is highly stressful. Back in the '70s, before I met my husband, I dated a musician when I first moved up to Nashville. I learned through him about how prevalent drug usage is in that business. He went on tour and started using "uppers" to get himself energized for the show after a day spent on a tour bus. Then he would have to take "downers" to be able to sleep on the bus after the show. He got addicted to this cycle, and it messed with his personality. It was easy easy easy for him to get prescription drugs, because there was a doctor in Nashville who would prescribe pretty much whatever the musicians said they wanted or needed. I know my experience was a long time ago, but I don't really think anything has changed. The drugs may have changed, but not the prevalence of them, or the way it works.
And show business is a very difficult life. Performers work from gig to gig and are always having to hustle to find work, even if they are lucky enough to be working. They work on nights and holidays when other people are off having fun, and they get their days & nights switched around. (I broke up with that boyfriend in part because he would keep me out at clubs until 4 am, then sleep all day; but I was a student and had to be in class at 9 am. His schedule wasn't working for me.)
People who are trying to make it in show business are under stress because of the lack of money and work. People who make it big, like Whitney Houston, are under stress for different reasons, I believe. Being successful doesn't do away with the stress. It just brings a different kind of stress.
I have always been a singer myself, so I do enjoy music very much. However, I decided a long time ago that it is better to use music as an adjunct in your life rather than as a career focus. I think the same goes for acting. You can always find outlets to sing and act in your community. You don't need to stake your whole life on the performing arts.