Lame Cliche at the end
The whole 'woman misinterprets something and can't be reasoned with so the guy must really go out of his way to apologize even though she is wrong' plot point is a staple for poor romance movies.
His ex kissed him for 1 second while they were on their first(barely)date. Then she immediately loses her sh!t, refuses to speak to him and quits her job? She had already been on a date in the meantime of when he began to fall for her. Just lame. It was a peck, it could have been a greeting kiss. Such a hypocrite. Hell 1 minute earlier her own boss tried to screw her and make out with her, is it beyond the scope of her mind that she's not the only person in the world who people make advances on?
The whole "Do you trust me?" line at the end was just over the top. Clearly the bitch doesn't trust you, she saw something for a second from 50 feet away and immediately changed her life and condemned you without any chance of redemption. She'd probably toss herself out a window if his mother shows up and gives him a hug.