In Joyce's "The Boarding House," it is clear that Mr. Doran is a serious-minded, industrious, careful young man ("All his long years of service gone for nothing! All his industry and diligence thrown away!") and not given to waste, frivolity or violence ("the family would look down on her ... disreputable father"). Joyce carefully contrasts him to Polly's brother Jack, who has taken after his rough and uncouth father ("thick bulldog face and a pair of thick short arms ... Jack kept shouting ... he'd bloody well put his teeth down [the artiste's] throat").
Based on Mr. Doran's character traits and on his narrated thought "Perhaps they could be happy together," there is every indication that James Joyce is giving us good grounds for thinking they will be happy, although there is direct evidence for Mr. Doran thinking he was intentionally manipulated ("He had a notion that he was being had"), which can breed a hot-bed of resentment. In addition, if Polly follows after her mother to the same degree that Jack follows after their father, then the worst Mr. Doran will get out of the deal is an efficient industriousness and native sagacity for a shrewd deal, providing he can overlook her ill-spoken vulgar grammar ("She was a little vulgar; some times she said "I seen" and "If I had've known."").
I don't think so. I don't think it will be successful. This marriage happens only because of the need of mrs. Mooni which Doran couldn't ignore due to the social system in Dublin. it is evident she traps him ("counted all her cards again") ("She was sure she would win") It was a battle for her to win on behalf of his daughter. This is not a love based marriage. We see how Doran was seduced by Polly.
Having nothing to do he marries Polly. If he didnt he would face a load of problems like loosing job and reputation which he had earned. He knew for sure he'd be accused for this fault, he was matured so he had no excuse. Religion was so strict and dubliners were known all the faults of other people, may be Doran didn't want to subjected to those gossips.That's why he agreed for the marriage, that is hinted by the final portion of the story (Mr. Doran wants to speak to you) He notices her wrong grammer, means he doesnt love her, who will care the little faults of a lover?
Polly seems immatured here, she's a flirt and who can say she has true feeling for this person?
Anyway both seem not in love, they have to marry due to social forces. I don't think Doran would leave her after marriage cause he's society concious. (not rakish or loud voiced like others)
But they wouldn't be happy together. There are no shadows of a happy marriage illustrated.