You should respect your significant other's privacy
Ken is recently suspicious of his wife, Helen, and thinks she might be having an affair.
Ken wants to find out if Helen is faithful.
Ken goes up to Helen and asks her if she's still in love with him or having an affair.
Ken goes into Helen's diary and reads it to see if she might be mentioning an affair.
Helen vehemently denies any affair and professes her love for Ken and is glad he cares about their relationship so much.
Helen is infuriated he's reading her private thoughts and feels utterly violated.