Lost a best friend cause I'm in a relationship.

Okay; my best friend and I been friends since jr yr in high school. Every relationship she been in. She kinda forgot about me until something bad happens. Her last the guy used and played her. I was still by her side. 
Me I didn't have any good relationships. Until I met my boyfriend i am with now. She's pissed off at me cause I couldn't go to her bday party cause I work 10hr shifts and I'm tired after work but I told her I would see her and celebrate with her but she said no. And she hasn't talked to me since October 14th her bday. 
Plus she's pissed cause I'm in a relationship and it's healthy. And she said she's never pick a guy over me. But she has and I haven't. Every time I tried to hang with her she had things already planned. So I'd just hang out with my boyfriend. He's becoming my best friend . 
I miss her. But I am not gonna deal with the bs. I miss having girls to hang out with and shopping with. What should I do?