The Five Year Engagement actress, who is married to The Office star John Krasinski, said that she finds relationships to be "complicated" and in need of constant upkeep.
"Life is complicated and shape-shifting all the time and you have to be willing to roll with the punches. The main thing that I find hard to learn as a British person is communication," Blunt joked to Celebuzz.
"If you are in a relationship, you have to talk to each other and you have to be forever generous… The best relationships that I have seen of my friends, and hopefully that I am in, is that you can't clip each others wings. You have to really empower the other [person] to be everything they can be."
Blunt went on to say that she and Krasinski keep their relationship strong by continually supporting one another's success and giving each other space to pursue their own interests.
"I do think the relationships where one partner is stifled by the others' success, it's either because they are allowing themselves to be that or they are sort of martyring themselves in some way. I think that is usually an unhealthy thing," she explained.
"Some kind of self-fulfillment is really important even if it means you have to spend some time apart and you make sacrifices in other ways.
"I think both people have to have some kind of purpose, some kind of identity. You don't want to end up defining yourself by association with someone else."
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