, use "is" if the person remains while in the part/partnership you are referring to, and "was" if they are not in that function/romantic relationship anymore. This means which the speaker is referring to an alternate that did not come about, but must have -- a sort of the subjunctive. https://www.jowissa.com/products/leather-watch-band-with-swiss-flower-embroidery-e3-1376-s