Steve and Mary are married and then get a divorce. Steve then marries Rachel, and they get a divorce, too. Steve remarries Mary and lives with her until she dies. After Mary's death, Steve marries Beth and lives with her until his death. These relationships of Steve's life are an example of

The answer is serial monogamy.
Explanation:
A person known as a "serial monogamist" will spend little to no time single, as they exchange romantic partners with unusual frequence.
Serial monogamy also implies commitment to the current partner, even though the relationships might not last long. Some studies have found that this behaviour provides a sense of security and stability, as it relates to the brief and changing nature of human emotions.

Honestly, let me think. i'm .