"Ok, maybe it is not a boundary since there is nothing I can do about it if it is not respected."
No it IS a boundary. Boundaries are for you. It tells her what you will not tolerate. True she may step over them, but they exist to tell her what YOU will not allow.
To a certain extent, boundaries should come with consequences and you follow through on them. Some of the threads that people have mention them threatening legal action as an example. Find what that consequence can be. You have to start thinking like the WAS and not really care about her feelings.
Remember...detach.
Keep those boundaries. It's putting yourself in the driver's seat and not as the victim.
You need to figure out what the consequences of the boundaries are and follow thru with those. I always think of myself as a mother of 3 year old child (exh) and I say don't do that or ???, then he does it anyway but nothing happens. I say it again and again and he keeps doing it knowing I won't do anything. Need to draw the line and stick to it, not keep backing up the line. Figure out what the consequences are.
Me: 46 FWS: 36 Married and Divorced 4/07, Pregnant 7/07,False R 7/07 Baby Girl born 3/08 Kicked him out because OW: 7/08 5/10 He realized what he had and lost. Moved home! REMARRIED 3/14/11!!