He stayed when Farrah bought herself an engagement ring and insisted he pay her back for it and then use it to propose to her.
He stayed with her through meltdown after meltdown, and goodness knows she's had plenty of them.
They've broken up, gotten back together, only to break up again ... it's been a mess.
And although the two of them just went on a romantic vacation together just two months ago, it looks like they're actually done for good this time.
Earlier this month, Simon announced that MTV is airing a Being Simon special soon, and that it would be the last time he'd appear anywhere in the Teen Mom franchise.
Farrah then tweeted that he's not in her life anymore "and is really hurt I moved on."
She also advised him to stop talking about her.
"You're pathetic," she told him, "and I'm a great mother, professional, friend & women. Go STOP using me for money!"
She tweeted several more messages about him, including some screenshots from texts in which he called her a "rude pig" and sent her photos of a new car he'd bought.
Then Simon, who'd previously shared several photos of himself with a new girl, tweeted "Farrah sees me happy with a beautiful woman and sends me a cease and desist letter! Lol wtf?"
It was all very, very strange, but thanks to a new interview Farrah did with Us Weekly, we have more details.
First off, her lawyer confirms that Simon was in fact sent a cease and desist letter -- but not because he got a new girlfriend.