It might be. What is certain is that it is not governing. It is in two fights; for its own survival and for the survival of Brexit. Let us look at each, starting with Brexit.
Outside the government there is now a general consensus in the UK as a whole, in parliament and in the EU as a whole, that the only way to avoid serious economic damage to both the UK and the EU from Brexit, is that membership of the customs union and the single market continue. This includes the continuing integrity of the United Kingdom. Because any attempt to offer a separate status to NI which did not cover the rest of the UK would, as we saw through the deadlock of negotiations on Monday last, be unacceptable to the DUP, which props up the government. It would also provoke a demand for the same from Scotland, Wales and London.
Conversely any attempt by May to offer exactly that equivalence, or whatever word you want to use, of regulation between all parts of the UK and the EU, would provoke outright hostility from hard Brexiteers and Cabinet resignations. In other words May is cornered. There are three immediate prospects. The first is a fudge sufficient to enable negotiations about trade to begin and hold the May government together, but, like all fudges, this will simply defer the day of reckoning. The second is the collapse of the negotiations, leading to a policy of a hard Brexit. Both of those will eventually lead to the collapse of the May government anyway and with that, of Brexit itself.
Nobody bothered to think through or investigate the feasibility of Britain’s exit from the unification of every strand of national life within the EU. Of course it could be done but the costs and complexities are way beyond anything anybody is willing to pay or undertake. Brexit, in the terms upon which people were offered it in the referendum and by a narrow majority backed, was never in reality there. Had the real thing been offered it would have been overwhelmingly rejected. So the trumpeted mandate for Brexit was, in truth, a con. Eventually cons are caught out. Truth, one way or another, has an enduring capacity to win through.