A third-person story with a change of love interest.
I'm a lovesick fool. I've spent five years chasing after a scumbag, and I finally got him to agree to marry me. But on the day of our engagement party, his old flame returned from abroad, and he ditched the ceremony to pick them up.
With a crowd of scornful onlookers watching, the scumbag's assistant drove me home. The song "There's a Kind of Love Called Letting Go" was playing in the car. I thought, maybe it's time for me to let go, too.
Just then, I heard the assistant, who wore gold-rimmed glasses and rarely said more than necessary, mutter, "Wait, is this a world where same-sex marriage is legal?"
Me: "?"
I went to a bar to drink myself into oblivion. The scumbag's assistant found me and rescued me from some other people. I asked if the scumbag cared about me, and if that was why he'd sent him to save me.
The assistant replied in his usual irritatingly businesslike tone: "No. The boss just asked me to find out when you plan to move out. Your things make his old flame uncomfortable."
After the assistant took me home, drunk out of my mind, I heard him mutter again, "Is this some kind of broken-window effect? Seeing him like this makes even me want to bully him a little. No, I'm a law-abiding citizen."
I finally gave up. I told the assistant he didn't need to come see me again.
As I left, I heard him grumble, "A textbook case of the pathetic bottom finally waking up. Wonder how long it'll last."
Then the scumbag suddenly came to see me. He said he didn't love his old flame, he loved me, and he hoped I'd change my mind.
I heard the assistant grumble again: "Couldn't get the old flame, so he's settling for the next best thing?"
Suddenly, I didn't want to be the next best thing.
Later, the scumbag told me he never asked me to move my things out, and he never brought his old flame home. He'd even tried to come see me several times, but the assistant told him he couldn't find out where I was.
The scumbag's assistant came to stand before me, too. He said the scumbag had been so consumed by romance that the company had lost tens of billions. He'd taken over the mess, transformed the company, and turned its losses into profits. Now he was a domineering CEO himself, and he asked if I'd be willing to be with him.
Me: "Is this the plot where the second male lead gets the girl?"
Him: "."
Theme: Become a better version of yourself and find a better love.