Writing Research - Love (Romantic not sensual)

This weeks emotion is Love (Romantic not sensual). What mannerisms or behaviors do you associate with romantic love?

Here are some prompting questions.

How do you know someone is in love?

What do they do that indicates they are in love?

What do they say and how do they say it?

Do they have involuntary responses?

Is there a physical response to Romantic Love that only the person experiencing it is aware of?

Please do not leave any input that involves sexual or sensual responses, mannerisms, or behaviors. I will not publish any comments containing this type of information and I want to be able to publish all comments.
All insight on romantic love is appreciated!