"your responsible for how i feel, now you had better be doing the right things so that i can be happy"
This has less to do with jealousy, monogamy, or polyamory to me than with EMOTIONAL MATURITY.
Taking emotional responsibility for oneself and not shooshing it on to others with blameshifting tactics and so on... that's one of the stages of emotional maturity.
One stops saying things like "You make me feel____" and replaces it with "I feel _____." One assumes responsibility for their own emotional management.
A person can look grown up on the outside, but be in different places in each of the six maturities.