Erotic romance about a powerful controlling man playing a game

[Stupid]

Please help! I read this I believe 3-book series between 2012-2019. The series is a pretty popular one.

I do not recall the characters' names, but here is what I remember:

- The male character is a powerful rich man, who owns a bar and/or a restaurant, among other things.
- The main female character works there.
- The man has an ex (a close family friend) and they are playing a game, where he is supposed to make the main girl fall in love with him.
- The man has a sister - a very positive character. She is a clothes designer and has a boutique. Her name might be starting with an M.
- There is an erotic scene in a dressing room.
- The guy takes the girl to the Hamptons, where his family is vacationing. The mother does not approve of her.
- The guy claims his ex was pregnant with his baby and had a miscarriage, but in fact, the ex was impregnated by his father, with whom she had an affair.
- The girl finds out about the game her boyfriend and his ex are playing. He swears it started out as a game, but he fell in love with her.
- The ex tries to interfere any way she can and play mind games with the girl.
- The sister asks the main girl to be a model for her clothes at an event.
- The two main characters might have gotten married at the end (I can't remember for sure).

I would be so grateful if anyone can help. Thank you!