I had this issue and it was a weird one.
I summoned a familar in camp and rested, the familar died and still shown above my warlock. After summoning the familar again it shown 2 familiars, a dead one and one with full HP. However when I summoned the familar the entire party lost -5 standing towards the familar upon summon. After resummoning the familar a few times I returned to rest and the familar was attacked by the dog and the vampire geezer. As the familar was in my party they attacked me too. A few more summons and I had no companions left. This corrects if you load a save game.
This happened with my ranger and giant spider on an earler playthough.
