Well, 'one love fact vs fiction' could be about distinguishing real aspects of love from the made - up or false ideas. For example, the fact might be that love often requires effort and compromise, while the fiction could be the idea that love is always perfect and effortless.
It might be exploring the differences between what we know to be true in love and what we wrongly assume. The fact could be that true love endures through tough times. Fictionally, some people think love is only about passion that fades quickly. It's a comparison of the real nature of love against the misconceptions.