But how quickly things can change in the world of reality television.
During the "After the Final Rose" special, which aired immediately following the season finale, Jason dumped Melissa on national TV in lieu of a shot at re-connecting with runner-up Molly Malaney – the woman he cut loose prior to proposing to Melissa.
But, according to Jason, it wasn't up to him to break Melissa's heart in front of a TV audience of millions – it was how the producers of the reality show wanted it to play out.
"That was part of the deal. I signed up for it in my contract," Jason told People on Tuesday. "Your relationship is – good and bad – in front of everybody…. If I could have, I would have seen Melissa the night before. It killed me. It kills me now."
In the time between his "Bachelor" proposal and the "After the Final Rose" show (which was actually taped six weeks ago), several weeks had passed, during which time
Jason and Melissa lived in different cities, but spoke often and spent the holidays together, the couple explained on last night's wrap-up.
"It feels different… The chemistry is different," Jason explained to host Chris Harrison during the show, prior to bringing Melissa out on stage to call off the engagement.
Once Melissa was brought out, and Jason revealed he was breaking up with the 25-year-old sales associate, a visibly emotional Melissa fought back tears as she voiced her frustration.
"You put a ring on [my] finger… You should get engaged once in your life and you stole that from me… You should've just let me go [on the finale]," Melissa scolded Jason. "You are such a bastard."
"Melissa and I just have different ways of communicating. We're not right for each other," Jason told People after the show, not revealing any other details behind the split.
Of course, Jason, the 32-year-old single dad from Seattle, has also found himself on the wrong end of an ABC proposal – "Bachelorette" DeAnna Pappas broke Jason's heart last year, choosing Jesse Csincsak over him to be her fiance (an engagement which has also since been called off).
After a tearful Melissa left the stage, telling Jason, "Don't call me. Don't text me anymore. Leave me alone please," runner-up Molly was brought out for a one-on-one with host Chris Harrison, where she professed she still had feelings for Jason and was hopeful he would one day "change his mind."
Jason joined Molly and Chris on the stage and revealed he had just broken up with Melissa in hopes of a shot with Molly.
And while "Bachelor" runners-up of seasons past have appeared on the wrap-up show full of anger and questions that needed answers, Molly's shock at the news quickly turned to joy, as she told Jason she "dreamed" this would happen, and the two even began to kiss on the same couch where Jason called off his engagement just minutes before.
"I think we can see where things go," Molly smiled.
"There was part of me that wanted things to work out with Melissa so bad. But the whole other piece was I had these crazy feelings for Molly," Jason told People. "I didn't say something right away because I wanted to figure out what was going in inside of me."
And while both Jason and Molly insisted they had not seen or spoken to each other since Jason dumped Molly on the finale in New Zealand, AccessHollywood.com's "Dish of Salt" Laura Saltman has heard otherwise.
As previously reported in her blog prior to Monday's finale, the "Bachelor" and the runner-up had been seeing quite a bit of each other – while Jason was still engaged to Melissa.
"I spoke to my source who revealed that apparently Jason had been seeing Molly behind Melissa's back the whole time and that ABC [was] going to play it off like he had a 'change of heart' to the fans and the media," Laura wrote. "In a series of e-mails, the source obtained (which have also made their way onto the Internet), Jason apologizes to Melissa for hurting her. My source has spoken to Melissa to try to get a sense of how she is holding up but she would not reveal anything."
As far as the "switcheroo" storyline goes, the source told Laura that "Jason went along for the ride hook, line and sinker… at the expense of Melissa."
Related Content from AccessHollywood.com:
PLAY IT NOW: Dish Of Salt: Meet 'The Bachelor' - Jason Mesnick, Part I
PLAY IT NOW: Dish Of Salt: Meet 'The Bachelor' - Jason Mesnick, Part II