Hello and Welcome to the forums!
I am also the hinge in a MFM cohabitating Vee. MrS (my husband) and Dude (my boyfriend) were/are best friends and we live together as "chosen family". A lesson I had to learn over our first years has been that fair=/= equal. They need different things/attention from me at different times. Communication is key.
I'm glad that you found us and would be happy to talk more.
Me: poly bi female, in an "open-but-not-looking" Vee-plus with -
MrS: hetero polyflexible male, live-in husband (together 21+ yrs)
Dude: hetero poly male, live-in boyfriend (together 3 yrs) and MrS's best friend
Lotus: poly bi female, "it's complicated" relationships with Dude/JaneQ/MrS; married to TT, poly male
VV and MsJ: bi-women with male primaries, LTR LDR FWBs to JaneQ
My poly blogs on this site:
The Journey of JaneQSmythe
The Notebook of JaneQSmythe