Walden runs into his ex-wife Bridget at a singles mixer on Two and a Half Men. "Throgwarten Middle School Mysteries" is the 17th episode of the show's tenth season.
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Two and a Half Men Season 10 Episode 17 Quotes

I am the CEO of a pharmaceutical company, so every time you get an erection, you owe me 10 dollars. See, sense of humor.

Sylvia

Walden: I am a failure
.
Lyndsey: No, you are not, but you looked like one in college... I would not have slept with you, and I slept with everyone.