I have two things to say to you:

First one: now I know why I feel what I feel when I see you and her together. I'm jealous, I'm jealous of you being with her instead of me.
I didn't knew this part of me, since little ago I didn't knew what I was really feeling. But if I'm jealous is because a reason, I want you to be mine and only mine. Without having to share you with anybody else. I'm not naïve or silly, I know this will never happen because I would never make you do something that you don't want to do.

But despite what I have just said never happens I have realised something else. I love you. I know I have told you this before, but I really love you. More than you think, more than I would ever have thought. I don't want to lose you. I don't care if you hurt me, I don't care if you don't love me the way I do. I don't want to leave your side ever again. I want you to count on me if you need anything. I want you to know that I will always be by your side. I would rather let you use me than leave you. I don't care with how many people I will have to share you if I can be with you even just a seconds. Because I know these seconds will be the best of all.