How to fix relationship with goddaughter?

Hi everyone,

I’m 29F, and I’ve been a godparent for 4 years now. They’re all siblings and their ages & genders are: 4F, 9F, 11F, and 15F.

The kids are unfortunately not in the best living situation (emotionally) and I would say their mom is their first bully. Last year the 15F really confided in me and it broke my heart. She didn’t want me to talk to her mom about how she felt but I felt awful just being a bystander. I had an honest conversation with the mom and told her things from my pov. I truly feel like once the kids are grown they’ll cut ties with their mom and I thought if I talked to the mom that she’ll realize she needs to make a change.

Unfortunately my talk didn’t go well because once I left the mom lashed out verbally towards 15F. I’ve apologized to 15F for that situation but since then she’s been on the fence about telling me things (which I get to an extent). I haven’t had a heart to heart with their mom since the incident because there’s no point.

Fast forward from last year to last week. 15F was angry at her mom, was slamming doors and cussing. I asked her in a calm tone if she wanted to talk about it and that’s when she called me a rat in front of her younger siblings and said she learned her lesson not to talk to me. I was hurt ofc but I didn’t say anything until we were in private.

I told her she can be upset and that I’m here to help and be in her corner but the name calling isn’t okay. She said I’ve never been in her corner and she never asked me to do any of the things that I’ve done for her. I told her that I do those things because I care about her and she said to just focus on her younger siblings. I left after that. She sends me a Snapchat streak everyday but besides that I haven’t heard from her since that conversation. What do you guys think is the best approach in this situation? Should I continue to give her space? Should I reach out and offer to take her out for lunch and talk one on one? Or just leave it alone?

Just for understanding, some things I’ve done as a godparent: visit them almost every weekend, take them out to eat (they don’t get to go to restaurants), bring them to community events, attend parent teacher conferences, take them shopping, attend birthday parties, I was the only one that attended her cheer games for 2 seasons, take her to school when she misses the bus, take her to her friend’s house, etc.