Good quick tests of whether an Intimacy is balanced:
1) Is this an emotion, belief, or similar that people actually have, or that people-like creatures could conceivably has? In this case, answer is a yes.
2) Can you, the hypothetical ST, imagine an influence roll the Intimacy would penalize Resolve on? In this case, the first thing that comes to mind is "fight/betray/screw over your friends, and I let you live/help you out," so yeah.
Some useful bits in the book that provide more depth on this are the sidebar on page 172 and the description of intensities on page 215.