Pebbles....remember this part: Boundaries are to protect you. It is your job to enforce the boundaries. They are not "rules" that the other party has to go by.
They have the right to any reaction they choose to take (or "try" to take). their reaction is their problem. Your job is to enforce the boundary if they step over it.
Usually, there is a lot of unhappiness when you establish a boundary. The other party will usually try to sabotage it in any way they can. They will try to push any button that they can.
You have to do what you have to do...just don't be surprised if there is no co-operation from the other side....
dandylion