Playing the HRE aswell. I am well aware of the declining diplomatic standing with most (if not all...) of the kingdoms surrounding me. The trick is to pick a main ally and keep paying a regular tribute to them so your standing with them dont decrease.

Aswell as doing the same thing with the Papacy ofcourse. That is, until you descide to realize the Holy Roman dream and take your beloved Rome back

From a HRE perspective the world is filled to the brim with dirty backstabbing kings on all fronts. They hate your guts and all you can do is brace yourself and retaliate. Ive been backstabbed by just about every half-witted, inbred, rabblerousing king out there hehehehe.... And I love it.

Currently allied with the Byzantine Empire and have been so for around 40 rounds. My borders are closing in on theirs fast so my guess is they will feel uncomfortable in about 5-6 turns.