Bassanio is very close to both his friend Antonio and his wife Portia. Though Portia and Antonio love one another for Bassanio’s sake, there is some unspoken, possibly unconscious, competition between the two. Antonio and Portia have given much to Bassanio. Antonio gave Bassanio money so he could woo Portia, putting his life on the line to borrow money for him. Portia was willing to give Bassanio lots of money to rescue Antonio and, when that didn’t work, disguised herself as a lawyer and almost single-handedly saved Antonio’s life.
During the trial, Antonio asks Bassanio to speak well of him to Portia. Bassanio says that he would sacrifice “life itself, my wife, and all the world” to free Antonio. Unbeknownst to Bassanio, Portia is there. She comments, “Your wife would give you little thanks for that, / If she were by, to hear you make the offer.” As a kind of payback, Portia insists Bassanio give her their wedding ring as payment. Bassanio protests until Antonio suggests it is fair to give him the ring: “Let his deservings and my love withal / Be valued against your wife's commandment.”
In the final scene, Act V, Scene 1, Portia condemns Bassanio for giving away their ring and even tricks him into thinking she slept with the lawyer to get it back. Antonio feels awkward about these quarrels, but Portia insists it is not his fault:
ANTONIO: I am the unhappy subject of these quarrels.
PORTIA: Sir, grieve not you; you are welcome notwithstanding.
She eventually reveals to Bassanio that she was the lawyer and tells Antonio that he has regained his fortune. Though Portia and Antonio have a kind of a subtle power struggle over Bassanio, they are reconciled in the end.