She couldn’t marry Townshend because at the time the royal family didn’t allow divorcees to marry into the family, the Church of England and Parliament wouldn’t approve the marriage
Now, she did cheat on her eventual husband with a bunch of guys, one of whom committed suicide after they broke up. She also had this young boy toy she would fly out to her private island in the West Indies
Peter Townsend was shady as f uck. It was bad enough that he started messing around with Margaret when she was 16 years to his 32 years. The girl he went on to marry was a good 25 years younger than him. When they got married, he was 45 years to her 20 years. Definitely a pattern.