And there is clearly no role for a marriage guidance counsellor.
At times on Radio Wales this morning, the party's health spokesman Rhun ap Iorwerth spoke with the kind of tone normally reserved for obituaries.
When he came close to speculating about a future relationship between Lord Elis-Thomas and Labour, you got a sense of the bad feeling this is going to cause.
But the real zinger from Plaid is the accusation that he has misled the voters in Dwyfor Meirionnydd, and the call for a by-election.
Ironically, after years of bad feeling, particularly between him and the leader Leanne Wood, things had appeared to be getting better.
To say he has been a thorn in the side of the party is an understatement, particularly for Plaid who have been looking to mirror the iron discipline which has been such a feature of the SNP.
The first time I witnessed his trouble-making close-up was a Plaid conference in 2014 when Leanne Wood said in her speech that a vote for UKIP was a vote against Wales, which he described as facile.
The comment had particular bite because it suggested a degree of superficiality in her speech.
Senior figures in the party were furious with him, and that mistrust never went away.
As we have seen with Nathan Gill's departure from the UKIP group at the Senedd, it does not take long for internal splits to develop in this assembly term.
There are potentially big implications for the assembly.
Labour narrowly missed out on an overall majority, and with two floating votes up for grabs in the form of Lord Elis-Thomas and Nathan Gill, Plaid and the Tories may find it more difficult to put the squeeze on Labour.
Having said that, Labour has formal mechanisms in place with Plaid to discuss the budget, Brexit, legislation and the constitution so there's likely to be a willingness to make that work.
But nevertheless, Lord Elis-Thomas' eventual divorce from Plaid marks a major development in Welsh politics.
After a turbulent marriage, the divorce papers between Lord Dafydd Elis-Thomas and Plaid Cymru have been filed.