fall out of love

fall out of love (with sb/sth) — разлюбить, перестать любить

Example 5: One day everything was perfectly normal, and the next he was gone. Apparently by choice and without a word of explanation. Even now, Grace had difficulty believing that the man she'd lived with, the man she'd loved, and with whom she'd had two daughters, could do anything as cruel as this. If Dan had fallen out of love with her, she could accept that. She would've found enough pride, enough generosity, to release him without bitterness. If he was that miserable in their marriage, she would've gladly set him free to find happiness with someone else. What she couldn't forgive was the misery he'd heaped on their family's shoulders, what he'd done to their daughters. (Debbie Macomber, 204 Rosewood Lane,2002)

Example 6: As you know, the press is fickle. They may fall in love but they can also fall out of love. It's a long campaign.

[go off sth]

(starting to fall in love with someone)
fall for sb — влюбиться
Also fall in love with sb

I think I’m falling for Jeff. He is such an amazing person. I want to be with him forever! (englishbaby.com)