I truly believe Mincheol from the past was a good lover. But sadly, he took her for granted as time went on. Growing up without his parents, he learned to act and speak in ways that earned him affection to fill that emotional void. However, when the FL gave him unconditional love, something he wasn’t used to, something he didn't even understand, he stopped putting in any effort. Her depression, caused by his debts and neglect, made him see their relationship as a failure, something he silently hated and resented. He didn’t try to properly communicate and even took advantage of her low self esteem and money. In his mind, moving on (through adultery) was the solution. The best way to move on from this failure of his...Well, Mincheol, regret is all you’ll have from now on, and no one can save you from it.