Q. I am a 20-year-old woman who has been in a two-year relationship with a guy who has been my good friend for seven years.

Last summer, we were apart for three months when I moved across the country for an internship.

Things were rough, I was very lonely and I had a drunken one-night stand. I didn’t care about the person, I was just lonely. I feel so guilty. I never told my boyfriend about my infidelity. If I didn’t tell him, he would most likely never find out.

I hate that I did something that would hurt him intensely. I was a friend through his years in foster care and the incarceration of both of his parents.

I have been the shoulder to cry on and his support system.

I betrayed the most important person in my life and failed him miserably. I have seen people cause him pain and I don’t want to be the cause of more.

I want to be with this man for the rest of my life, but I also accept that it would be entirely my fault if I told him and he left. I feel a lot of guilt and shame, but the thought of his face after I tell him makes me feel like my heart is being ripped out of my chest.

What do you think I should do?

Torn

A. You are 20 years old. First of all, if (illegal) drinking leads to such regrettable behavior, then you shouldn’t do it.

Ask yourself: If your boyfriend did the exact same thing that you did during your separation (a one-night stand), would you want to know about it? Does this episode speak to some sort of deep-seated problem or need that you have, or was it a stupid mistake made by a young person that will never be repeated?

If it is the former, you should realize that you are not quite ready to be in a long-term, exclusive, and committed relationship. If it was the latter, then you should keep this to yourself.

This might be one of those times when you should carry your own guilt privately rather than relieve it by unloading onto your boyfriend and burdening him with the dilemma of what to do about your behavior. Carrying this burden and choosing to wise-up and behave differently is the consequence of this episode.

If you find that your guilt over this continues to interfere with your relationship, then you should tell your boyfriend. Do not expect him to appreciate your choice, applaud your unburdening, or forgive you right away.

One risk of having an outside sexual experience (even a one-night stand), is contracting an STD. You should visit your doctor or nearest Planned Parenthood clinic to be tested.

Q. My old college friend and former roommate is pregnant with her fourth child. We are not as close as we once were, but still keep in regular contact.

A family member of hers contacted me recently to ask if I would be willing to host a baby shower in her honor. My friend had difficulty getting pregnant this time around and so I am very happy for her blessing.

Her family lives out of town. Amy, I have co-hosted multiple parties and events for her and her family over the years (honoring engagements, weddings, graduations, etc.) and have never once had the favor returned. I did not even receive a congratulatory note when my own daughter was born, and invitations I extend to attend celebrations in my life get rejected.

Is there a way to politely refuse to serve as hostess? Should I put my hurt feelings aside in the name of friendship?

Feeling Bitter in Boston

A. Here is how you politely refuse this request: “I’m honored you asked me to host this shower, but unfortunately I can’t do it. I’m so excited for Barbara, I hope this pregnancy goes smoothly for her, and I wish her the very best.’’

Q. “Upset’’ was overly concerned about going with his wife to meet with a group of high school friends, including one she’d had a very brief relationship with.

His wife told him to “get over it.’’ She should have at least validated his feelings.

Gentle validation (’’I’m sorry you’re upset, but this is nothing for you to worry about’’) would work better.

A Reader

A. I agree. Thank you.

Amy Dickinson can be reached at askamy@amydickinson.com.