Hello, I am a solicitor with 20 years experience. I will try to answer this for you.
Is your home a self contained flat or a part of the landlord's home?
I assume that you are right that you are a regulated tenant. Most tenancies starting in 1982 were regulated with all the protections that includes. (my earlier query is to check that you are a tenant not along term lodger)
You can invite anyone you want to come and live with you at your home.