Being in love with someone is great. Being in love with someone who's in a relationship, not so great. Being in love with someone who's in a relationship while dating said person's sibling... well... you get the idea.
Have you ever fell inlove with someone? Ofcourse you did. And it comes to the point that it really hurts but still you does'nt have a plan to stop.
That it suffocates you but being with him is like better than living.