You have been listening to the thoughts of comrade Corbyn again haven't you.
Ditching N.I. isn't a new idea is it, the IRA tried force a United Ireland on the people without their consent and it turned into a bloodbath for all concerned.
Anyway the Belfast agreement was created to facilitate SF/IRA demands that the British should recognise that there are 2 separate communities in N.I., one Unionist and the other Nationalist.
This means that any future border poll would require a majority in both communities for a U.I.
So stop letting your anti Ulster prejudice cloud your judgement.
Remaining in the EU requires zero changes.
Simples