Theresa May spent two years saying that the UK would leave the customs union and the Single Market.. Now she is begging the EU for permission to remain in the Customs Union (oh it will now be called a "customs partnership"). She said that no deal is better than a bad deal but now she seems to have capitulated and is accepting that "any deal is better than no deal"..Her negotiating stance has been a complete joke and disaster. The incompetence and foolishness she has demonstrated is breath taking.
The Brexiteers hate her deal as it means the UK will follow EU rules and regulations, pay in cash to finance the EU and will end our ability to do trade deals with non EU countries that they fantasize about. In addition, the UK will become a "rule taker" following EU rules and regulations without any say in their formulation. Meanwhile remainers know that this deal while better than no deal is vastly inferior to remaining in the EU. As remaining in the EU gives us power in setting the rules, benefits the services sector (80%of the UK economy) and gives us a say in the formulation of rules and an ability to block things we do not like.
I do not believe she can get this deal through parliament in a "meaningful vote". I predict that she will lose the vote, she will be forced to resign and there will be a Peoples vote and the result will be a vote to remain. This will then lead to the revocation of Article 50. This mess is without precedent in UK history, the only way out is a second referendum to undo the “will of the people” in the first referendum.