Question for moms with older teens

[Mare]

Lately I have been very sad its like I miss Frankie even when he's right next to me. If I look at his baby pic I cry. I thought it was because of all the stress I've been going through lately. I spoke to my sister about my feelings and she said I'm mourning the lose of my child who is now grown up. She told me she got so depressed she had to put all her 17yr old sons pic's away. We were both pretty much single moms with just one child and had a very close bond with them. She thinks its because we were not done having kids both of us wanted more it just didn't work out that way. What I want to know is are there any other moms that feel this way or did and if so how did you deal with it???