1. A nightmare is when the hydraulics fail and people get hurt. What happened to OP isn't a nightmare.

2. People get overbooked and IDB every day. It's a fact of life.

3. Whether compensation is due and what it might be is a factual matter and OP hasn't provided any detail at all. Did OP check in on time, was she at the gate for boarding on time? What were the exact circumstances? By way of example, it sounds as if there was space for her, but she elected not to accept the seat because they couldn't get her husband on too. That's not an IDB, that's a voluntary rebook.

4. If OP comes back with facts, maybe she'll get help here.