1. When Ben had sex with his wife while his girlfriend was hidden in the closet in He's Just Not That Into You.
2. Erin almost killing herself in What Women Want.
3. When Vivian was almost sexually assaulted in Pretty Woman.
4. Karen discovering her husband's affair in Love Actually.
5. When Tim goes back in time to say goodbye to his dead dad in About Time.
7. When Olive's fake date forced himself on her in Easy A.
8. Amy's dad dying of an overdose in Trainwreck.
10. The timeline where Helen dies in Sliding Doors.
11. When it was revealed that Meryl cheated on Paul in Did You Hear About the Morgans?
13. When Emma died suddenly at the end of One Day.
14. When Matt was raped in 40 Days and 40 Nights.
15. Elle being propositioned by her professor in Legally Blonde.
17. Rosie's miscarriage in What to Expect When You're Expecting.
18. And finally, the strange ending of 50 First Dates.
Submissions have been edited for length and clarity.