Ok I get it now......I don't think it is punishing you are enforcing your personal boundaries.
If it was me I would pull way back, follow Sandi's rules. Only interact with her about finances and I guess your dogs. No small talk, no chit chat, only respond to actionable texts and if you have to respond to a text because she asks you a questions keep it short to Yes, no, sounds good, thank you, etc. Never initiate conversation unless it is absolutely critical. No excuses, hold the line.
I would pull back, head in the complete opposite direction. If she asks if anything is wrong say "No, everything is good" if she pushes further and asks why your being short or not as talkative etc. then you can let her know that while she is in an A with OM you will be keeping your interactions to strictly business which includes finances and the dogs.
I don't like just making the statement without her initiating the conversation first. Make sense?
She might not even ask......when I pulled way back my W never moved closer. She never inquired.