If you ignore the collective wisdom of the members of SI and think the way you're approaching this is the right way then prepare for a rude awakening, we have literally read thousands of stories like yours, no your WW is NOT special, her behavior is typical and right from the "Cheater's Handbook".
Things you need to R successfully:
1)NC FOREVER with OM, they work together so one of them needs to quit and find another job, if they keep in close proximity then the A will most likely go deep underground or resume in the future. Also have her send a NC FOREVER letter to OM, one that's approved by you (no sweet goodbyes) and then you watch her hit send.
2)EXPOSURE with OBS and ALL family and close friends (at least with both your parents if alive), yes she needs to apologize for her HUGE betrayal. Nothing kills an A faster than full EXPOSURE with OBS, plus you gain an extra set of eyes to help ensure NC and you can exchange info about the A, OBS may have access to messages your WW deleted on her phone/email.
3)DEMAND full on demand access to all her electronic devices and passwords FOREVER, no questions asked, there's no such a thing as "privacy" in a M other than toilet time.
4)Demand she gets tested for STDs (full panel), by this time you should know all CHEATERS LIE, TT and minimize, even if you think they haven't had sex yet (which you really don't know), plus there are STDs than can be transmitted via saliva, but make no mistake, adults involved in an A have sex when in close proximity, and lots of it, maybe you caught her on time, maybe not, but 8 weeks (could be much longer) is really a long time just to hold hands and a peck, I know you know there's more.
5) Demand she goes to IC to find out her "whys" with a counselor that specializes in infidelity (don't waste your money on MC for now), remember you were in the same M and you didn't cheat, problems in the M are 50/50, her A is 100% her fault, she made a DECISION to cheat.
6)She needs to show true remorse (not just regret), but your WW is far from being remorseful, she doesn't even accept it was an A and is lying and minimizing. In order for true remorse to start, she needs to HATE the A and not think of it as something "beautiful and romantic", the embarassement and guilt caused by full exposure helps with that.
7) Consult a D attorney to know your legal options, and have her sign a postnup with an infidelity clause in your favor, if she cheats again (She's now a proven cheater and liar), she leaves the M without alimony/spousal support and you keep the lion's share of marital assets.
8) Follow the advice of those who walked in your shoes before here in SI, don't be another poster than comes here sometime later with a "You guys were right" thread or somehting similar, there's a saying here in SI that "you have to be willing to end your M in order to save it" if it can be saved at all, and it proves true all the time.
If your WW is not willing to come clean and you find this is a dealbreaker for you, it's OK, transparency is at the forefront of a remorseful WS, if that's the case just file for D and have her served without warning, D takes a long time and it can be stopped before it's final if she comes around and shows true remorse, if D papers and full exposure don't shock her back to reality, then nothing will, either way you get out of infidelity.
Keep posting frequently, this is a crucial moment in your life