3rd mc after healthy pregnancy

So after getting my BFP this month, and having my doctor confirm it, I have miscarried again. This is my 3rd mc :( I don't understand it and can't believe how frustrated I feel. I have a 2 1/2 year old and got pregnant within 2 months of trying. Ever since DH and I started trying again, well over a year ago, we've had 3 mc. I have an appt to see an OB and maybe get some answers. I'm just wondering if I keep trying and keep miscarrying, maybe I should just come to realize it's not meant to be.