Thus far, there's no evidence that MM consulted a divorce lawyer and there's also no evidence that MM texted a friend she thought AM was acting fishy or that she wanted to meet AM at hospital versus going home to Moselle. I think if there was any evidence of divorce rumors, the state would have led with this information to support an additional financial motive.
In fact, evidence showed MM requested Bianca prepare a meal for the family before she left for the day. IMO, I think AM was being his usual opportunistic self when asking MM to leave Edisto where he was able to take it all in (last supper with the family) before the demise of his family forever.
Tonight, I heard a talking head suggest an interesting theory where there could have been a heat-of-passion altercation between AM and PM at the kennels where PM said/did something wreaking of irresponsibility that was about to cost $$$ AM further (after AM spent the day preparing for the wrongful death hearing, and then challenged by his firm), and AM lost it on PM and witnessed by MM.
If I were defending AM, I think I'd be considering something like this that ties to AM's state of mind on June 7 when he'd been subjected to a boatload of bad news. MOO