Wells, we talked a bit, you may take this wrong but it's just my opinion....
You found out she has a boyfriend, in my opinion I believe it is selfish of you to say how you completely feel and to use the word love. I say this because by doing that you only put her in a situation and stuck between a rock....
I fully believe it is a respect thing to her and the guy that those words should not be said while she is tied to another. In my opinion, as this whole thing is, if you truly cared, when you found out about the boyfriend the "wanting more" should of ended right there. How do you think you make her feel to say you love her while she has someone? That is selfish of you I feel.