If she's cheated on you right from the start of the marriage, something is very askew here. Why has she cheated? Maybe she never loved you in the first place? Was this a marriage of convenience at the time? How old are you both now?
I love solving problems that no one else can, it's my forte. While I would personally divorce her in a NY minute, rather than hang with her for 5 more years, maybe there's more here than we know and maybe it's salvageable for you two?
Who knows? Sounds like you two have some figuring out to do.....