The three pairs of lovers in act V of The Merchant of Venice are Lorenzo and Jessica, Bassanio and Portia, and Gratiano and Nerissa. The act opens with Lorenzo and Jessica, who seem very much in love and intoxicated with each other's presence. They make a game of recalling the adventures of famous couples of antiquity. Though it is true that all the love affairs they mention ended tragically, to make too much of this would be to mistake the playful spirit of their words. The games ends when Jessica says:
I would out-night you, did no body come;
But, hark, I hear the footing of a man.
This makes it clear that they have been engaged in a light-hearted competition between equals. The one aspect of Jessica which may shock a modern reader is her callous desertion of her father, but there is no reason to doubt her devotion to Lorenzo.
Much has been written about Bassanio's reasons for marrying Portia, but, though he is clearly interested in her money, there is every indication in the text that he loves her for herself as well. Unlike Lorenzo and Jessica, it is fair to say that Bassanio and Portia are well-suited to one another because they are not evenly matched. Portia is more intelligent and resourceful. She has brains enough for two, which is exactly the amount the wife of the feckless and irresponsible Bassanio will need. As ever, Gratiano and Nerissa are little more than echoes of Bassanio and Portia, though Gratiano cannot be accused of making a mercenary marriage.
The characters who are not loved or in love, and who make this ending rather awkward in spite of the three happy unions, are the absent Shylock and the present (if not exactly loquacious) Antonio, each of whom presents a lonely figure at the moment of general rejoicing.