BFF Help!!!!!?

Alrighty, so me and my BFF Veronica have been BFF's since the 1st grade (8th now). Anyway, recently she has been hanging out with other people. I mean, that doesnt bug me at all because in elementary school, we only were in the same cl once and we are still best friends. So i know that if she is hanging with other people it wont change our friendship. But, just about 2 weeks ago our school took a field trip 2 six flags and i was going 2 go with her. Then on the bus ride up there she completely ditched me and said she wanted 2 go with other people when we had this planned for like 3 weeks. Now, it was recently her birthday and i asked if she was having a party, she said no. Last night, my friend called and asked if i was going 2 her party which i wasnt invited 2. I dont mind that much not being invited, although it hurts, but its the fact that she lied 2 me and has been pushing me away and i dont know why. What do i do, I dont want 2 talk because i dont want 2 loose her completly??