Are "Selfless" People Inevitably Exploited?

I've been reading Boundaries -- Where You End And I Begin by Anne Katherine, M.A.  It's not as painful to read as some of the more useful self-help books, but still emotionally challenging at a more than superficial level.  Perhaps I am yet to fully comprehended the implications of what I have read.

Have you heard the saying "Screw me once, shame on you.  Screw me twice, shame on me."?  Anne Katherine offers a more precise, refined set of explainations about the related phenomena.  Perhaps with the right information, you could make an aphorism more suited to you.

Anne uses stories, ostensibly from her own clients, to give life to her technical observations. 

(from "Donna's Story" in Boundaries -- Where You End And I Begin, p.52)

     You know something?  I was never revered for giving myself away.  They treated me more like a brainless servant than a respected wife and mother. 

     When I remember that, it helps me keep going through even though they're so against me.  I'll be damned if I let anyone stop me now.  Even if they are the people I love most in the world.

To not exploit a person who behaves in such a way requires great self-knowledge, great personal strength, great emotional maturity.  And a person behaving in this manner does not give those around her or him the feedback that could facilitate awareness on the part of the other person that might give them the impetus to engage in "respect".  Was Donna behaving in this manner because she believed that she was doing her family a favor (or tons of favors)? 

If we haven't experienced this dynamic at home, we may experience it at work, especially if we have a position as a secretary or a nurse or some similar position, as Anne explains:

A subtle shift happens when one person in the relationship sees himself as setting the limits and doing the thinking.  He begins to see himself as more powerful and valuable.  Anyone who has worked in supportive services has experienced this. 

... This imbalance can cause the supportive partner to feel less important, less sure of her value and the worth of her ideas, more dependent... more enmeshed.

... Enmeshment means that someone's individuality is being squashed.  An enmeshed person is not known. 

(Boundaries -- Where You End And I Begin, pp. 61-63)

Does your spouse act like your boss?  Does your boss have the wisdom to treat you with respect?  Can you respect someone that you does not make their individuality known to you?  Do you know how to be simultaneously "selfless" and "compassionate"?