OP, I know how it feels to be attached to a certain horse whom you don't own & so knuckle under to pressure, even though you know that it's not best for the horse & yourself. Stop & think whether continuing is best for the horse. This is your moment of truth, to do what's best for this poor horse, who's caught in the middle of human egos.
And continuing with this dangerous scenario will either cause a wreck, & with owners not liking you, your time is short anyway. Ask me how I know this.
These situations suck, & seems like all the wrong people own horses sometimes; I do sympathize.