Did I commit a sin by not informing my wife and family about my dormant Hepatitis C infection before marriage, and is this virus considered one of the diseases that necessitate separation?

If the illness is not contagious and does not cause repulsion, then there is no need to inform the wife about it, and one does not sin by concealing it. However, if it is contagious, then marriage is not permissible without informing the wife, due to the harm involved. If the marriage has already taken place, she must be informed so that she can take protective measures. This illness is not considered one of the agreed-upon defects that grant the wife the right to annul the marriage, but some scholars have analogized to it every repulsive or contagious defect.