I find both emotional and physical cheating almost equally disturbing but I've always thought that physical cheating is the worst (I'm female). If someone breaks my heart, I can move on and get over the person but if they sleep with someone and catch something and I end up with herpes because they had to get their sexual satisfaction behind my back that would really infuriate me!
How do you move on from that?! The emotional cheating can hurt more but the physical cheating could lead to serious consequences that may potentially affect your life and health forever!
I was tempted once to cheat, it was purely physical but I decided not to because even though he would never find out, I knew that I would've broken the trust of someone I love and loves me and that simply isn't me. As bad as the urge can get for physical satisfaction I think, we as human beings, are able to and should rise above it.