There’s a few ways it can play out, ironically most of them depend on Labour.
If Labour votes for, or abstain from whatever Maybot comes back with, then it gets through Parliament regardless of how big a rebellion from either side of the Conservatives. The rump that will obey the whip will be sufficient to see it get through the House. Even if Labour abstain, that will be the case and Maybot will squeak through (even if the SNP voted against just for the hell of it).
If Labour votes against, then life gets interesting. May will not have the votes to carry any kind of deal through since what will appease the Hard Brexit faction will piss off the Remain faction and vice versa. The whole “dancing on the fence” act will eventually force her to land on the fence and end up with splinters. If it doesn’t navigate parliament then it automatically fails which means we default to the “No deal” scenario.
This is bad for everyone, not just the UK, because whilst the current rights of EU citizens will be covered for the time being, it’s also been made clear anyone who’s not been in the country for 5 years will no longer be able to get means-tested benefits, they have to default to contributory benefits only (which will kneecap a lot of the low skilled workers because they run on means-tested to get the benefits system to work). That’s going to force a lot of people (mostly EU2) to go back (something the EU really doesn’t want, nor does UK business to be fair since it means wages will have to rise to attract local nationals to work).
Then there’s the small issue of the £40 bn divorce bill which will end up in international arbitration for years. The EU might get their money, but it won’t be for an awfully long time. No deal also means the UK won’t be beholden to the transitional legislature (such as Article 13) so whilst the rest of the EU fucks their internet over, the UK will have a different sort of internet fuckery, but likely no link tax and likely no upstream internet censor filters to worry about.
That to me is the big one, if we’re out before Article 13 goes live and is enforced upon the EU, the UK gets an open goal to become the European (as in the continent) bastion of the Free Internet. In relative terms at least, we will be seeing as it’s not like you don’t get less surveilance elsewhere and you won’t have to file paperwork if you want to submit a goddamn meme.