there is not such an "uncle" in the poem "a servant to servants". the narrator refers to many characters -particularly her brother and her husband- both suffering from mental illness. the woman is also suffering because she does something to but she is not happy with the situation.
the poem has a dramatic monologue about the woman life's circumstances and her traumatic events form the past.
"a servant to servants" is a poem written by robert frost, and is part of a collection of poems "north of boston", of 1915.