Ungrateful Cousin

Long story short, my parents have been letting my cousin(18-21) stay with us for the summer. I(17-18) play guitar, my cousin sometimes likes to listen, I said "would you be interested in learning anything?" She said "yes I want to learn bass." I asked her, "if I got you a bass, would you be willing to learn it?" She said yes. So a few weeks later I got her one(just got bass, no amp yet for her). 2 days ago I showed her the bass she said she would start practicing and let me show her how to play it on Tuesday(yesterday) but she wanted to go "shopping" so she never practiced. On Monday she drove us to a music store so she could try out some bass amps, I asked her what her price range was(I was not planning on buying her an amp, she was gonna buy her own) she said anything under $100, so we saw 2 really good ones... one was $60 and another was $25. I asked her which one she wanted she said "they're both too expensive." I said "even the $25 one?" She said yes. After that she said "let's stop here(clothing store)" she ended up(and I only saw because obviously I was at checkout with her). $145 on numerous pairs of clothes. Still hasn't picked up the bass I got her. Is she ungrateful?

I think she should thank you for buying a bass for her but it sounds to me like she wasn't serious when she said she wanted to learn bass. Have you ever heard people say "I'd like to speak French" or "I'd like to learn to ski" but these are passive statements? It means they would like to do that but it's not a priority or something they intend to do right off. Alternately if you asked her, she might not have wanted to hurt your feelings. This sounds like what your cousin is doing. Best wishes.