me & my so-called best friend were planning a baby shower for my sister who lives 160 miles away we were?

we were having it at 7:pm on sat.The morning of shower she stayed the night all ready to go with me. I asked her to go to the drug store for last minute items.So I gave her $30 and she left and never returned . I waited and waited for her. Finally I had to leave.Its now a week later and I still havent heard from her. No apology no nouthing. I'm so mad at her. I even washed and waxed her car the day before so her car would look good. She said she was gona help do this and that. I knew nouthing about giving a shower . She was all gun -ho , she was the shower expert . So now she cant even call me . I know nouthing had happened to her because other friends have seen her.one even asked herto ride over with him to visit me ,and she said hell no. we were getting along great.and this is how she treats me. What would you do or say the next time we see each other?