Woman expects friend to keep affair a secret

DEAR HARRIETTE: My friend expects me to hide her affair from her husband. She recently confessed to me that she has been seeing someone for a whole year. I asked her why she won’t just get a divorce, and she said she doesn’t want to because she still loves her husband. I am extremely disappointed in my friend because I thought she had better values than this. She’s been married to her husband for 10 years, and I consider him my friend as well. What makes this situation even more difficult is that her husband has always been kind to her and supportive of their relationship. As far as I know, he has no idea what is going on, and I feel terrible knowing that someone I care about is being deceived.