I just had a miscarriage and i am very sad about it, i cry all the time. but the weird thing is that i am extremely horny, what is happening? this is so weird, i am devastated, but i want sex?

Sex is a natural event that provides comfort and gratification on many levels. Thinking about the sadness of your loss is a separate issue. I would not link the natural sexual urges to achieve comfort as anything more than your body telling you you need comfort. The link to reproduction is a side effect of sexuality and the natural drive to reproduce is why it can be so strong. No guilt needed.