My Dad was 74 when he got married the second time. My mother passed away in 2009 and he just did not like being alone. He started volunteering at the senior center and meals on wheels. He met a wonderful woman and two years later, they were married. I am the only one of his children that didn't pitch a fit over it.
I'm only 62 and still married. My husband is considerably older and starting to develop health problems that might or might not lead to his death. At worst, his retinal melanoma could kill him in 6 months; at best, coming from a long-lived family, he may outlive me.
If I were single again, I'm not sure whether I would prefer to stay that way or would like to find another life-mate. I certainly would not settle for just anyone available; it would have to be someone very special.
I have met people who started relationships as late as seventy. My mother's best friend was 72 when she met an 82-year-old and later married him. A girlfriend who is 71 married her 83 year-old boyfriend last year. A 74-year-old neighbour, a male aged care nurse, abandoned his wife of fifty years to marry the much older widow of his recently deceased client - strictly unethical - so he left the agency he worked for to avoid telling them.
I am 73 and comfortable with being single. I'm not actively looking for a mate, but if I happened to meet someone compatible, I would consider a serious relationship.