I asked Bing AI if they were romantically involved, and he said no, they're incapable of feeling love or emotion. That shows AI programs know nothing about love.
I have another theory. It's possible they were together back when they were in the solar system, but split up and now are separated and growing apart in interstellar space.
BTW Voyager 1 is male and Voyager 2 is female. So all the ingredients are there. Whether they split up due to infertility caused by the intense radiation of space is another issue.