I have 2 dds aged 8 and 6, and I had a third dd who passed away in October aged 13 months. Until she died, I had had a baby, toddler or preschooler at home since I was 23. When she died, I felt like not only was my darling girl gone which was the worst torment, but added to that I'd had that whole period of my life whipped out from underneath me. Suddenly I had 2 older girls who, lovely as they are, really don't need me that much!
Added to that, as I was fairly young when I started my family, my close friends are only just starting to have their first babies now in their late twenties, early thirties. I find that I don't really fit in anymore as my children are older and I can't really share stories of sleepless nights, weaning and baby groups etc. I find myself feeling very jealous of pregnant women and those with babies, because I miss my dd3 and wish I still had her, and was still enjoying that period of life.
I have worked part time up until now as I always had a preschool aged child, but now I have no one to care for during the day, I've made the decision to go back to work full time in September (I'm a teacher). I'm okay with the decision, but I know it's a poor substitute for being needed at home. 
How do I move on from these feelings? Does anyone else miss the preschool stage? Please tell me what might help me to look on the bright side.