On his lip u mean his mouth right? If its on his mouth the only way he would of gottin it is giving oral sex to someone that has herpes type 2 on there genitals. Type 2 is usually not on the mouth its usually on the genitals only. When its on the mouth its very hard to spread from there. If he has a sore on his mouth then yes he can pass it but otherwise i highly dought he would pass it to u. Now if it was on his genitals that would be differant. There are some people that do not catch it that way either. They are lucky. With one partner having herpes & the other not having it. Its hard to say what happened whether he cheated or not. i have type 1 & 2. Do i think he cheated its possible. He should not be having an outbreak on his mouth. The only reason he should be having one is if hes stressed out mabye went threw a surgery or something or he cheated & thats how it got there. Sit & chat with him. I mean its possible mabye hes had this for 24 yrs & didnt know but mabye he had surgery & his immune system weakened. He could of cheated to. I have no idea with this case. If u would like to chat message me.