To continue the story as seen on screen:
The newly awake woman is wooed by the desperately lonely man. They go on a date. He shows her around. He tells the bartender not to mention that he woke her up. The bartender, an android without feelings, agrees. He’s about to ask her to marry him and the android tells her.
She gets angry and accuses him of murder.
They live apart for a year.
Malfunctions start to happen on the ship.
One day, in an effort to make things up to her, he creates a tree (somehow) in the middle of the main part of the ship. She thinks it’s cool.
Then someone says ‘Why the hell is there a tree on my main deck?’ and they rush to the main deck and find an awakened crew member.
So the awakened crew member gets them into the command area. He’s sick, but says “it’s just post-cryogenic sleep hangover” as if it happens all the time. I guess it is standard for crews to sleep for 120 or more years, wake up for a few months, and then sleep again. Rinse and repeat. Hell of a jet lag. I think they’d all be crazy. In Paladin of Souls, by Lois McMaster Bujold, one of her characters is put under a spell and is only awake for an hour a day – when he has to eat and drink and void. The rest of the time, he’s asleep and it messes with his perception of time. Peeps need a consistent sense of time passing otherwise the brains get messed.
Anyway – hero tells the crew member he woke up the girl because he was so lonely. Crew member doesn’t really have an opinion about it because he’s trying to keep the ship from blowing up. Girl tells the crew member that hero woke her up, says it was murder. Crew member says “a drowning man will pull down others” as if that explains the selfishness of the hero.
So, crew member tells them how to fix the ship, gives them his pass code, and then dies.
Can you say “Deus ex machina“?

So, hero and heroine find the problem (an asteroid blew a hole through the computer) and discover an additional problem, the ship is really going to blow up if the pressure is not released. Hero goes out to fix it with a flimsy interior heat shield thing while girl hangs on to the venting mechanism. He goes out of the ship to the vent, but can’t keep it open. So instead of using his heat shield, he tells her – “vent anyway”
She of course says “no, I can’t live without you” which is probably true since (as mentioned before) she has no mechanical/technical skills to speak of.
This is his selfless act that is to redeem him.
She vents because she’d fry if she didn’t. He lives but gets blown into space.
She goes out and rescues him and puts him in the medical pod.
It fixes him.
It turns out the medical pod can be used as a normal cryo-pod and one of them can sleep again until the ship arrives. He offers it to her.
Cut scene
Next scene, he’s alone in the bar with the bartender. She comes in. He gives her the ring.
and Ever After but not a satisfying ending.

Other things that could have happened in this movie to make it better next time on Passengers part 3