Jealousy issue

Okay so there is this girl i know who is two years younger than me but acts older and has a mum that buys her everything she needs for horse riding. when i met her i she was just getting into horses and i was giving her tips and now she is already doing things i cant because my parents can't afford it. we are going to be put in the same group for riding but she is doing way better than me. We aren't friends because of our strong opinions but i don't want to be rude. Any advice please...