How to use "betrayed" in a sentence

He began to shake and he fell back into an armchair, feeling angry and betrayed

But a long time ago you were Stryker's mentor, the man he respected, the man he learned from, and now you've betrayed him

One thing is clear: he looked afraid when he saw me, so he has probably betrayed the Brotherhood; he probably thinks I'm following him so that I can kill him

If I discover that he has betrayed the Brotherhood, I'll have to act.'

The man you saw at the opera is a member of the Brotherhood and has betrayed the cause