Hi Niamh,
I feel like giving you a whopper of a hug.

I think your friend CA is having some problems . And shes not being the good friend she may have been in the past. She is acusing you and the other friend of hating her . and that hurts.
then she moves in on your budding relationship. and lets you know .
yes you have been betrayed and I see your doing what you need to do to move away but it STILL hurts and its a loss. A very big loss.
I think you may feel better if you can tell her that you feel betrayed and your friend ship meant a lot and you would never take a male freindship away from her . that this is a deal braker of sorts and sadens you to say goodby.
Geting these feelings out and expressing them to the person who has hurt you may relive your taking it out on yourself .
I wonder if you may feel like you didn;t take care of yourself
when you gave your male friends phone number to CA .
what you could have done was to call your male friend and ask him for the number and then give it to her. This would have not given her a shoe in.
but its not your fault for what she did.
Your so trusting . Im sorry your trust was violated .
And you sound like your not being heard or have no one to give you ideas on how to navagate this friend who is having some personality changes. even projecting her mistrustfulness on to you .
kinda crazey making to acuse you of hating her when shes moving in on her best frinds new hope for a boyfreind. they call that projection.
You may feel rejected and betrayed by both your best freind and this new male friend . almost like you are not there .
Don't disapear and please take care of your body . This hurts but you will make new friends.
Patricia