I have thought about what is different in this relationship from any of the others for both of you. Chemistry is one thing, and anyone who has experienced a strong attraction to someone that they just met knows what I'm talking about. It isn't just about looks, but that plays a part. And then there are values and beliefs that jive, or not. And love languages. That plays into relationships. You covered many bases with the charcuterie picnic, the art museum, the zoo, the flowers, the cookies, but something about you singing to her seemed to be what really spoke to her, but only after enough time has been spent and enjoyed between the two of you. It is like peeling the layers off of an onion, getting to the heart of each other.
And her gifts to you have been very personal and thoughtful, about the two of you.
And maybe it is all coming together for the two of you, who really deserve each other in what seems to be a great thing after all the hurts that life has thrown at both of you.