The fact is that Brexit divisions have settled in in the country, becoming more part of people's political identity than political party.
There's a complete lack of political leadership, with May saying what she thinks majority Tory supports want to hear, and Corbyn saying as little as possible to try and avoid making any decisions on Brexit, hoping May pushes Brexit through so that Tories can be blamed for any downside. Functionally, that means the two main parties are pro-Brexit, Tories vocally, Labour passively. With FPTP voting, there can only be two parties without vote splitting, so there's no functional political opposition to Brexit.
If Brexit does happen, well, Brexit won't be over; it's going to grind on for decades of negotiations trying to replace and replicate what the EU already did. Hopefully, that ultimately means coming back to the EU.
Why do I think Brexit probably needs to happen, though, even though I don't want it and it's not in my interest? Leavers won't understand the folly of Brexit until after it has happened. If it doesn't happen, it will poison politics for decades, and the UK would be even more obstructionist than it's been to date.
There hasn't been a positive identity-based case made for Remain. Everything has been framed as economic arguments, and in particular economic harm from leaving. Free movement - a reciprocal right of EU citizens - has been misleadingly framed as immigration. The history of UK joining the EEC has been rewritten and misremembered as joining a simple trade area that got out of hand. It's too late to turn these sentiments around, and there's no leadership trying to do it. In fact quite the opposite: because Tory membership is so pro-leave, Tory leadership contenders are all out-doing one another in EU-bashing.
None of the political leadership is thinking of the good of the country, everything is on the basis of party politics.
It's the kind of thing that helps you understand why world wars get started.