Hi Worn,
I think there's a trap many of us codependent survivors-of-Ns fall into...if we need to end a relationship we want to do that PERFECTLY.
I read a bunch of relationship and dating advice books at one time in my life and was quite amazed to find out that what's healthy, when you need to end something (and you do, even if you feel scared), is to say something like:
"I'm realizing that this relationship isn't really working for me. So I wish you well, but it's not working for me. And for me, not being in contact is the best way to move forward."
PERIOD. Not: here's what I hoped for, here's how I'm hurt, here's what's wrong (no point in doing that with someone who's not mature or well enough to meet you like a healthy adult to "work on it"), here's what this means to me, here's why I feel this way........
Nope. Just, "I've realized this isn't working for me, and I wish you well. So I'm saying goodbye now." Click. Hang up. Send.
There may be wails, threats, and pleas to "Change back!" but actually, you're not doing them any favors by rushing back to comfort them, and help them avoid their own discomfort.
You need to endure your own discomfort too. Healthy assertiveness (which is what ending an unhealthy relationship is) feels very uncomfortable and unnatural at first.
But it's AWESOMELY adult and will do wonders for your self-esteem.
If you need some bucking up before you do it, read up on Boundaries in Relationships. You can search the What Helps? forum here...they're there.
Let us know how it goes,
Hops