Sounds like a normal poly-person-learning-to-deal-with-reality situation to me, lol. Not to be flip! Just saying - many of us have been through what you're in the middle of and worse, some of us many times over. Relationships are hard. Poly ones are harder. Nothing new there!
+1 to those saying "talk to your partners and everyoine else can fuck the fuck off". Hell - my POLY friends frequently stuck their collective noses in our shit on a regular basis, and it often caused issues in our FMFF "quad" - AND WE ALL LIVED TOGETHER! WHen there's distance compounding communication issues, this complicates further a complicated issue - and people sniffing around and stirring pots doesn't help.
Consider the source. If said source isn;t one of your partners, consider it a lot less.