[pantalaimon]

You still need a reason to regularly take them in the first place, before the physical addiction kicks in.

[hhmc]

I still remain unconvinced that loneliness is the primary precursor for alcohol, opiates, etc.

[H99189]

I've heard from (a random Youtube video) that opiates mimic/activate some of the same brain circuits as pleasant socializing.

[somenewacc]

For opiates, the reason is often being prescribed them for pain.