Getting disheartened

I don’t get how so many people get pregnant after a miscarriage! My periods have been all over the place since my miscarriage in April. I had 1 normal 28 day cycle and was due on again on the 3rd August and I just got my period mid cycle. When will it end 😭😭😭😭 it does not help my sister in law just found out she’s pregnant and she wasn’t even trying. I’ve been trying for over a year and sadly lost my first in April. I just want to break down 😭😭😭😭