I somehow managed to become hostile with my own faction ("the followers"). I'm not sure at what point did it happen though, I only noticed it by accident when my smuggling activity caused the relations to drop even further and they became inhospitable to me. Is there any log of relationship change against player somewhere? And it seems "the followers" aren't present in the "Factions" tab at all so I can't even see their relationship with me and other factions.
I loaded the previous save where the relationship with the followers was still at 100 (BTW, the only way I found to see your relationship with your own faction is via "Special functions" -> "Prisoner actions" -> "Repatriate prisoner").
In that save my faction has formed an alliance with Diable Avionics, probably because I was at "cooperative" with them - I was in their faction before leaving and starting my own.
What happened after that save is that I have attacked a Diable planet. The pact has dissolved, and looks like the relationship drop has happened at that point, with Diable *and* my own faction simultaneously.
Interestingly the newly captured planet doesn't want to trade with me, citing "my recent hostile actions around it" and it will be "many months" until the commotion dies down. How screwed up is it?

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