...one again with the same guy? My girlfriend had a miscarriage in October and now i Just found out shes pregnant again, whats the possiblility she'll have one again

Just slightly elevated from the normal odds of having one, which is thought to be about 25% (as in 25% of all pregnancies end in miscarriage). The reason that number seems really high is that many people miscarry without even knowing they were pregnant to begin with.

That's pretty hard to calculate, as each pregnancy is different, even with the same people involved, and there are so many possible reasons the first one that you may never know...just hope for the best...good luck to you all!