Alright Ladies Feel Free to Chyme In . .

What is a good way to approach another women about a 3 way relationship? Im currently in a realtionship with my childrens father , as in my fiance . I recently expressed how i wanted to be with women again as i have in inbetween our on n off stages . He recommended i get a girlfriend and insisted that i do what makes me happy , but still acknowledge and set down boundaries that he is still in the picture so ive been looking and some women js arent ready for that , arent willing to step out of a comfortzone or something . But im willing to step outside of my comfortzone as well and welcome another person into my personal life . It would be a first for myself . Ive came across a girl i like and i want to pursue but how do I approach her with out scarying her off ? Or making her uncomfortable?