Cancer man with Cancer woman and Leo woman

by Maria

I'm a Leo girl and I was with a Cancer guy for over a year. At about 6 months in, we decided to go poly with a Cancer girl. Now it's devolved into poly-gone-wrong with her mood swings and my inability to play second fiddle. She's fragile and constantly down on herself and has very poor coping skills. He can't choose between us and I think it's just that he's really drawn to her up-and-down emotional states. It keeps him more interested. And it's really rough to handle. I love the gentleness and romance that a Cancer can bring, but are they just unable to commit?