Is my Brussels Griffon sad?

I have a Brussels Griffon. She is almost 2yrs. I know griffons are supposed to be emotional but she seems sad all the time. She is way different than anything I read about the breed except her color and size. She never barks or growls. She is super friendly. She is especially clingy to me and seems sadder when I go to work or go to the store and I can't take her. If I take her anywhere I have to have someone drive me because she has to sit on my lap. I can't even use my laptop without her sitting on it or next to it. I worry about if I let her have puppies would she hurt them if I show attention to them. This is stuff I can't see on any web site. I love my dog and her unique personality but is any of this normal? I think she believes I'm her real mom and she thinks she's human. Can dogs get separation anxiety? When I leave her home she is with my boyfriend and my son whom both get jealous that my dog obviously loves me more than them and when I give her extra attention as well.