Love is always about two people, and a relationship is always the will, desires and decisions of two people, and not one specifically. If one man gives his woman to another (the woman's will, desire and decision were not even mentioned in the question), then his feelings and attitudes towards this woman can obviously be firmly questioned. Naturally, there may be exceptions, for example, as the film "Long Engagement" was mentioned above, but this is a difficult situation and here in the first place is the love of a man for a woman, as a person, and not as a life partner. Naturally, there is a "relationship" like that of Beauvoir and Sartre, that is, "Fuck even with a rhinoceros, just don't fuck my brains and let me smoke in peace." Relationships in the style of freelaw are always fix, because it's just a fit of two people to each other, but what's the point in talking about love after so many years of shame? It's just naive!
If they both wanted it, then it may well be.
Love is not identical with the absolute monopoly of time, feelings and the human body. What matters is how this particular couple perceives love.