Hey Pandas, Is It Bad To Have A Crush On My Friend´s Boyfriend?

A little background: I have loved this boy (we will call him E) for 4 years,and my friend (R) has never expressed any interest in E. Certain suspicious things have occurred and I have confronted both of them and both claimed to not have feelings for each other,this made me quite happy because E is single. But then,E texts me saying that R and him are dating, is it okay that I still am crushing on him????