Help!!!!

I’ve been feeling really sad lately when I see other people announcing pregnancy on social media.. this phase just recently started back. I’m happy for them no doubt but it makes me sad bcuz I lost my 1st baby and since have had another and baby’s soon to be 4.... so many people in my family and my boyfriends family have been telling me I need to give my baby a sibling but it’s hard. No one knows what I go through. I’m now currently loosing weight and I want to lose more but I’m feeling like I’m stressing or depressing because I get really sad and cry a lot now.