stay or go

I'm 21. I'm with a guy for almost 3 years. I love him with all my heart. But he has baby momma who obviously hates the fuck outta me. I try to ignore it but I can't. She is nice then a bitch and it's a constant bipolar type issue with her. And I can tell she is deeply in love with him like I am. Me and him NEVER get time to be alone. We never have time to just hang out. Maybe once a week if even!!! She has him wrapped around her finger it seems. I can't deal with the fact me and him never get to be alone. NEVER. Should I stay and hope eventually he will see that I want to have a little more than once a week with him. Or leave and hope there is someone else who has time. His daughter is fine. She is a really good little girl. I have no problem with her. it's just his baby momma who is taking time from us.