One of my friends (MO) was best friends with a guy and they were inseperable. It was clear that they liked eachother. so after a few months of literally hanging out every single day, she told him she like him and he stopped talking to her. The end.
so.. i guess the answer to your question is yes it is possible even though it seemed like he was in love with her…
At the same time, not all guys are like that..