“I love you,” isn’t necessarily a romantic sentiment. “I love you,” can mean all types of things.
I want to tell you “I love you,” because it feels important to tell people that they are loved, and someone telling you directly that you are loved by them seems like it could give a lot of comfort.
Though if you panic instead, that doesn’t seem like it would bring comfort.
I suppose my urge to tell you “I love you” is an urge to wrap you in the burning thought of a strongest hug.
I want to convey that I think you are worthy of care, that I want you to feel loved, that you are beautiful, that I am so glad I have you in my life, that you push me and comfort me in ways I’ve never gotten to explore, that I would be there for you if you let me.
I want to give you a kiss on the forehead and see you smile, pleased and content.