Help feeling sad

I'm 24 weeks pregnant with my 3rd baby, its a girl so exciting!!

Lately I can't control my emotions, 2 weeks ago I lost my 39yr cousin he died from colitis, he was married with a 4yr old. Watching everything unfold was so sad. The funeral was last Monday then Tuesday we had a wedding rehearsal both my boys were ring boys...Friday the wedding all so emotional because it was for my husband's cousins wedding, my husband's Uncle (same cousins dad) Died suddenly last September so im sure you can imagine all the emotions at these events....now it won't leave me its all im thinking about is how old I will be in 30years when my kids are in their 30's will I still be here will my parents be around....i had a dream last night my dad had a heart attack right in front of me...i can't stop crying...i was telling my boys how much I love them and how happy they make me and I just started thinking about losing them or them losing me or us losing my husband and I start crying...i can't stop worrying about all of this. Its so hard to even write this as I'm crying as I do, anyone else going through this? I didn't mention but I'm 38yrs old i was 33yrs old when I had my first baby and 35yrs for my second.

Thanks