At first good then disappointing

At the beginning I liked this drama because the chemistry was quite good and relations between friends were real. Suddenly it turned out that male lead and friends of female lead made a fool of female lead and she wasn't even angry at them. She was just so stupid and didn't have her own opinion, useless. But when male lead found out that she lied to him, he treated her like a trash. It was really annoying. He should have begged her for forgiveness or at least said sorry and she should have more pride.
I am really disappointed.