What is this personality split I'm feeling since practicing Vipassana?
I would say dont bother with any of them. Simply note them as mental formations. They belong to the 4th aggregate and are under the effect of the 3 signs of existence.

Note them and see how they arise and cease like all other conditioned phenomena. There is no "self" experiencing this - there is only the arising and cessation of mental and physical phenomena.

Dont identify with them. Dont take ownership of them. These phenomena are impersonal and empty of any substance.

You should look up Conventional &amp; Ultimate reality - Sammuti sacca &amp; Paramattha sacca.

Or

Check out the discourse on the Anattalakkhana Sutta by Mahasi Sayadaw. In this discourse it is described thoroughly and in detail why the 5 aggregates cannot be taken as a "self".