Married men spend most of their time with their wives, while single men hang out with their buddies. So, naturally, this leads to drinking and doing some other bad things.
Studies also show that married men are healthier than single ones.
For example, now married men live longer, they are less depressed and less likely to have a heart attack.
Psychologically you are better off being married. This is because you always have someone to support you, and you have a lover and friend, two for one. Another thing is that you become more confident once you are married.