What does it mean- she was forced in her own right?

There is something missing ...

This is incomprehensible as it is, without a context. Can you explain more? Give us the whole sentence or paragraph, or explain the circumstances.

Having seen your comment now, I wonder if perhaps it means "a queen who was A FORCE in her own right." In other words, she was a queen through (presumably) inheritance - not because she was married to a king - and was a powerful one.

That sentence has no meaning. Possibly you mean "She was a force in her own right", meaning that she had much power in the part of the world in which she operated.

Not totally clear without the full context. She was obliged, she had to do whatever it was the guy is talking about. the "in her own right" is an explanation for what makes her do that thing. her own personal needs are why she had to do that thing, and it was in response to an attack on her needs. A protective reaction. He did this, so she had to do that or lose something important.

It means the writer was a non-English speaker possibly trying to say she had a forceful personality or had some political power.

It doesnt mean anything. You cannot be "forced in your own right"

it means she had the advantage.