I walked in on my mother in a very compromising position. She let out a squeal. I'll never see her the same way again: DEAR JANE

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Dear Jane,

I was visiting my parents and staying with them for a week when I accidentally walked in on my mom in a compromising position – and I don't think our relationship will ever be the same.

That morning, I told her I was seeing some old friends and would be out most of the day, but when my plans were canceled, I returned to my parents' house earlier than expected.

But when I opened the door I could hear what sounded like two people talking – a man and woman. It was the middle of the afternoon, and I knew my mom was home, but my dad was still at work.

I followed the voices upstairs to their bedroom and opened the door to find my mom in bed with another man.

To make matters worse, it was my dad's best friend.

I screamed, she screamed, then I slammed the door shut and ran to my own room to process what I had just witnessed. She followed me profusely apologizing.

She said is unhappy in her marriage, and this affair had been going on for years - but my dad had no idea. She begged me not to say anything, promising she would tell him soon, but as the weeks dragged on, she still hasn't confessed.

I feel so guilty knowing this secret and have a feeling she'll take this to her grave if I let her. I don't want to blow up their marriage, but I can't carry around the burden of their affair any longer. 

Do I give her an ultimatum and another chance to fess up, or do I just out her secret to my dad?

Sincerely,

Disappointed daughter

International best-selling author Jane Green offers sage advice on readers' most burning issues in her agony aunt column

Dear disappointed daughter,

What a horrible double whammy. It's bad enough to have walked in on a parent, but to also discover her infidelity must feel like the ultimate betrayal.

Indeed, she has put you in an untenable position. 

Begging you to keep her secret is a terrible burden to place on you. It is not your job to be the mediator between your parents, nor should it be your responsibility to keep this secret.

It will only take a toll on you, and it's wrong for her to ask you to do that.

If your parents' marriage blows up as a result of your father learning about this affair, know that is not your fault. Your mother's behavior is to blame.

Ultimatums are only effective if you are absolutely willing to follow through. You are correct in wanting to set a clear boundary - your mother should be the one to tell your father. 

But given that she has already reneged, I am guessing that she does not believe there will be any consequences to her staying silent and sweeping this under the rug.

Give your mother a limited time to tell your father herself. If she does not, let her know that you will tell him, not because you want to hurt her, but because not doing so would cause irreparable damage to your relationship not only with him, but also her.

If indeed you are the one to tell him, know this: you didn't cause this situation, you can't control it and you are not the one to fix it.

Dear Jane,

I love the finer things in life – designer bags, expensive clothes and five-star hotels.

That's why I was crestfallen when I stumbled upon what I can only assume is my lackluster engagement ring in my boyfriend's sock drawer when putting away our laundry.

We only recently started discussing the topic of marriage, and he asked about what kind of ring I'd want. I sent him so many ideas – none of which resembled the measly rock in his dresser drawer.

It leaves little to be desired: a one carat, solitaire diamond atop a thin gold band. I would have preferred something with multiple gens in the setting, and a center stone at least twice the size.

I don't know when he's going to pop the question, but, as shallow as it sounds, I am certain that I will be embarrassed to wear that ring.

I can't possibly tell him that I found it, but to save us both the humiliation, I'm debating whether to drop not-so-subtle hints about the kind of ring I want and give him the opportunity to return it.

The only other option is to pretend I love it and count down the days until we can upgrade the diamond – but I would hate lying to my soon-to-be spouse.

What is the right way forward?

Sincerely,

Rocky engagement

Dear Rocky engagement,

When we assume, we run into trouble. 

You are jumping to all sorts of conclusions with little evidence that this is an engagement ring. For all you know this may be a family heirloom, or a grandmother's ring.

The best option here is to bring him with to the jewelry store to actually show him.

Tell him that when it comes to an engagement ring, you don't like surprises and do not want to be presented with a ring you haven't chosen. 

Say that if he is serious about proposing, you would prefer to visit a jeweler together, try on rings and give him a shortlist of the ones you love. 

That way, he can still surprise you with whichever of those rings is his favorite, knowing that he won't disappoint you.

But I would not tell him that you discovered a ring that you believe is not worthy of you. There is a good chance he would see you as spoiled and ungrateful.

Better, then, to keep quiet about the discovery, and ensure that he makes a choice that you both know you will love.