if you say that you're thirsty and really need a glass of water, and a person that cares about you gets up and gets you a steak, should you be grateful?  you politely say no thank you, and then they insist you eat the steak, adding potatoes and veggies, telling you how juicy it is and how much the steak is good for you with its iron and protein, and how no one else can even afford steak in the restaurant you're in, how you're really missing out.  And now that it's been ordered, you'd really make them feel bad for paying for it, after all they did it for you.  Then they order a few more steaks for you to go, and the waiter says what a wonderful person they are and so thoughtful too.  Do you still politely say no thank you?  Or do you get up and get a glass of water and dodge this person as best you can.

(hint it's a metaphor for people who don't care about boundaries or listening to the person they care about, because of narcissism that is socially reinforced.)