There is an act called the Harmful Digital Communications Act which says that there are principles which apply which I set out below
The communication principles are—
A digital communication should not disclose sensitive personal facts about an individual.
A digital communication should not be threatening, intimidating, or menacing.
A digital communication should not be grossly offensive to a reasonable person in the position of the affected individual.
A digital communication should not be indecent or obscene.
A digital communication should not be used to harass an individual.
A digital communication should not make a false allegation.
The penalties can be a prosecution in the District Court where:-
(2)In any case, a District Court must not grant an application from an applicant referred to insection 11(1)(a), (b), or (c) for an order under section 18 or 19 unless it is satisfied that—
(a)there has been a threatened serious breach, a serious breach, or a repeated breach of 1 or more communication principles; and
(b)the breach has caused or is likely to cause harm to an individual.
Your situation is unlikely to to come up to the serious threshold, because among other matters, it is true. If the police know this was you they may want to have a discussion so i would be careful in this situation.
There is also however a crime of using a computer system for a disnhoest purpose, in section 249 which says,
Every one is liable to imprisonment for a term not exceeding 5 years who, directly or indirectly, accesses any computer system with intent, dishonestly or by deception, and without claim of right,—
(a)to obtain any property, privilege, service, pecuniary advantage, benefit, or valuable consideration; or
(b)to cause loss to any other person.
Setting up a false facebook page may come under this section. So if you want to talk to the police i would suggest you find out if they want to charge you, and if so, only speak to them with your lawyer present.