Miscarriage question.

So I have had a miscarriage 3 weeks into my pregnancy.

I totally feel like it's my fault and I could have prevented it. I don't know why, but I do.

Like: was it the tiny bit of wine I had? That hike? I took ibuprofen.. was that it?

I have had 2 kids already and they were awesome pregnancies. So why the hell now?

I got diagnosed with Graves disease and an auto immune disorder. My body is treating itself like a disease and is attacking itself.

I feel like my world is crumbling. I know I wasn't pregnant very long but I put all my eggs in a basket and set myself up for dissapointment.

How do those of you who have had multiple miscarriages, or even just 1, keep trying?

I feel like totally giving up and finding the nearest cliff.