Have you ever planned to get with a girl but?

have you ever planned to ask a girl out weeks after the first time you saw her only to find out she already has a boyfriend? I saw a pretty girl at my job but I almost never see her. I work 8-5 and she comes in at 5. I made small chit chat with her two times only. And have planned since then to one day have a decent conversation and ask her out for coffee or something, but today I overheard one of my coworkers say that she was talking to her boyfriend on the phone. I was in a good mood but when I heard that my mood instantly changed to a sad and disappointed one. This isn't a very important issue compared to what other people are going through but I just wanted to unload on someone and see if anyone can relate