My friend (30) asked me (34) to be her bridesmaid and I?m not sure how to respond

We have been friends for about 4 years. After a traumatic event playing sports (neck injury/face injury), she helped me get back into a sport I loved. She was very patient, positive and kind. She was initially my trainer/coach but eventually became my friend as well. Earlier this year in January, I paid her for 4 lessons but I only received 1. She had a whole schedule planned out, but she cancelled. After I paid in advance. I had been paying in advance for 3 years so I had no reservations at the time. I had to cancel twice due to issues out of my control and she cancelled 2-3 times. Then, her truck broke down and she lives 1.5 hours away now so I just figured it would get fixed soon. I reached out in like August and asked if she planned to come out for any additional lessons and she said her truck was still broken. When I asked her to pay back the $150, she said she didn?t have the money to pay me back. Meanwhile, she has worked all summer and has gone to competitions, but told me she could barely afford to pay her bills. I was hurt for a long time, but less hurt now.
However, we haven?t had a meaningful conversation in over 6 months. Like, we have sent videos back and forth which sometimes we reply, sometimes she doesn?t. I got a random text message 2 days ago of her asking me to be a bridesmaid. She said she sent a gift/ask in the mail but it got lost so she texted me instead.
My partner says I will regret it more if I don?t do it but I?m not so sure.
TL;DR A previously good friend asked me to be their bridesmaid and I don?t feel excited about it. How do I respond?


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