Dealing with an ongoing affair

[PeterV2]

I've been thinking. Is there any value in calling the OM and asking him if his W knows he having an A with my W. Or is there any benefit to me calling the OM's W and asking her if she knows.
Because I know they were already involved in the A before he separated from his W. Or is that pursuing?
I've been out of town for a couple of days and when I came home she sent me a text saying she had hoped I would have dropped by her place on my way home. She had put her car in the shop while I was away and she picked it up late yesterday. She probably tried to put the $3000 repair bill on our joint credit card and was unsuccessful because the card in now maxed out. So she would have had no choice but to pay for it herself. She sent me a text saying "I picked up my car from the mechanic's". She wouldn't have sent me such a mundane text unless there was a significant underpinning.
I've been pumping thousands of dollars into her business over the past 5 months from my business and I'm wondering if I should stop doing that, just saying that I don't have the money this month. But I could still pay for my MIL's immigration lawyer because that's my MIL and I love her dearly. I don't really want her MIL to see a lot of tension in our M just before she leaves. So maybe I'll be prince charming for the next 4 weeks. But I must stay detached so as not to fall under the sway of W's charms. I expect her to be charming in MIL's presence, while having to wear my spew jacket when out of MIL's earshot.