That is going to have to be your decision, but remember the old saying, once a cheater, always a cheater. Do you think you will ever be able to totally trust him again? If the answer is no, then you should not get back with him.
Yes! Go back to him. Go for it. So you'll learn the hard way... If you value your morals so much to doubt them and actually ask question that is an apparent no.... You seem to wan to learn the hard way.
Aren't you a little more special than that? Do you believe that you deserve to be lied to? Exposed to disease? Have your trust broken? If you think that's what your love is worth go back. That is the lesson he will learn and he won't think twice the next time he does it to you. You will have taught him what you think you deserve.
Noo, you do not deserve to be cheated on. But then again, it's your decision. ask yourself if you like him thaaaat much to let it happen again? Or who knows, you think he'll be different this time around? But what >I< would do,is not date him.