in shock

i checked my husbands phone and i found some unexpected messages.  it seems that he had or is having an affair.  and w/ someone i know.  i cant believe it.  i dont know how 2 feel or what 2 do.  im hurt and angry. i fl like a punk.  i dont wanna leave.  he says he cares 4 her.  but he wants 2 b with me.  what the hell? i feel numb.  i wish id never found out.  more than the cheating, the lying hurts alot.  i thought we had an honest relationship.  i have asked him more than once if he was cheating.  and he always sd no.  im so hurt.  what do i do with that.