whew.
THIS is not a fun thing to discover.

technically speaking, youre right, you should wait until she's been working a while at the better job before filing.
so her income is higher, thus making your ss and cs less than if you filed now.

as far as her being at fault...no one (legally) really cares.
it's that 'no fault' thing.

i dont know about telling the guy's wife.
and IF you do...remember how you felt, and IF he's playing his cards right, his wife really could have no idea. (though she will suspect...women have a 6th sense about this stuff)
she, like you, is a victim.
she will suddenly have to deal with the emotional and finacial fallout of HER marriage falling apart.
And while, yes she should know for her own sake, do you want to be the one to tell her?
I hated hearing 3rd party about my stbx's escapades.
and if someones HUSBAND came and told me his wife was cheating with my (then) husband, well, i dont know.
it would have been awful.

im sorry you found out your spouse is cheating.
that's a burn, even if the person she's cheating with is an idiot.

i do not see how you'll be able to know this for months while she gets her career revamped and not say anything...

wont that be difficult?

too bad you didnt want to go to the marriage counselor before.
sounds like your wife kind of wanted to things to work out a while back....and looks like you Did need that outside help. even if it would have been for her...

get ready...this is a rough phase of your life youre about to enter.