Old Childern's Book
I'm trying to remember the name of a children's book I read when I was a kid. I cannot remember the name of the main character (and would also like to know that). The book is about some mice that live in a cafe of some sort. One mouse likes another (I think her name is Isabel or Isabella?) and he wants to ask her out for valentine's day but is too shy. He writes her lots of love letters and ends up crumpling them up and throwing them away. His best friend I think is named Theodore. In the end he trips on something and gives her a candy heart and they fall in love. The last page of the book has their tails making a heart. Please let me know if anyone knows the name of this book or the name of the main character in it. Greatly appreciated.