Mutual trust and respect are essential qualities for every long-term relationship.
But what if your partner loses trust in you when you did nothing wrong? How do you ever recover?
This is the challenging situation faced by one 24-year-old mum-of-three whose husband requested a paternity test after the birth of their third child.
While the test came back positive, she posted in the Relationships Advice thread on Reddit, about how their relationship has struggled ever since.
"My husband and I have three children; our sons look exactly like him but our daughter doesn't, she looks exactly like my great grandparents," the woman writes.
"From the moment he saw her, he told me he wanted a paternity test. At first, I refused because I felt it was humiliating and because I didn't think it was necessary because I never cheated on him.
"I hoped he would trust me but he didn't and for the first two months of our daughter's life, he made my life hell."
Watch: Reese Witherspoon on emotional abuse in relationships. Post continues below.
While their two boys have dark hair, eyes and skin, it was her daughter's blonde hair, pale skin and green eyes that elicited such shocking behaviour from her husband this time around.
"He didn't want to hold her even if she cried desperately... he never helped me with anything and that hurt me so much because with our boys he was completely different. He helped me all the time with absolutely everything and he was always there for me after giving birth [to the boys], but this time he left me alone.