Fight Fair? I don't think so.

Webster's Dictionary defines fight as "to contend in battle," whereas their definition of fair references "impartiality, honesty and freedom from self-interest, prejudice, or favoritism." That seals the deal for me! Fair fighting is an oxymoron. I vow never to suggest that fighting can, or should be fair. 

From where I stand, negotiation is a much more appropriate way to deal with relationship conflict.  Webster's says, to negotiate is, "to confer with another so as to arrive at the settlement of some matter."

All relationships, I repeat, every long lasting human interaction experiences conflict. Depending on your degree of investment in the relationship,  it may be worthwhile to go the distance in addressing it. 

When conflict arises, get face-to-face, with guard down, to discuss providing for the needs of one another. Negotiate.  

Unless, of course, you want the relationship to end, in which case fighting may be an option!