Hi so me and my gf have dated for 3 years, last month she wanted us to have a threesome with her best friend. When it was my turn with her friend we did doggy and she started screaming and came and her legs were just shaking non stop. It was amazing! My gf then said to me after that why can’t I make her scream like that or feel that way! She now wants to leave me because she says it seems I like her friend more and that maybe she just needs a bigger dick. I’m (9inches) btw, am I to small or is she jealous ?

Was it bad idea to have threesome with her friend ?