I Have a BFF but it feels like her new friend is stealing her. What do I do?

I have a Bff that ive known for over 3 years now. But this other girl is like stealing her away!! They've only known each other not even a year.I like that my friend is making new friends but whenever I try to do something wtih my bf the other girl is already with her and I cant join them cause there running off deep into recess!! I even try to play with her more but because of my my parents jobs i can't play with her as often. Now I dont even know what to say around her!! Maybe I try to play with other kids but apparently Im not popular at all. Now at recess I usually sit and do nothin. Help me!!