What's that word where one is so absorbed into the environment around them? [duplicate]

Solution 1:

Peer pressure could be the word you're looking for.

Peer pressure is influence on a peer group, observers or individual exerts that encourages others to change their attitudes, values, or behaviors to conform to groups.

Solution 2:

I think that you are describing what is often referred to as the bandwagon effect:

  • a phenomenon whereby the rate of uptake of beliefs, ideas, fads and trends increases the more that they have already been adopted by others.

(Wikipedia)