This is a tough call, or would be for me if I were in your place. I'm a little concerned about your assessment of the situation because you say she's distanced herself from you to keep you from finding out. Isn't this an assumption? How could you know this for sure, unless she told you?

If she's not ready to get/accept help, there's nothing you can do. If you put your friendship on the line & lose, then I gather she'll be left with no friends. Is that right?

Therapists are among the most difficult addicts to reach because they know all the tricks, think they have the most to lose, & deep down think they of all people ought to be able to help themselves.

When she reaches her bottom, if she's alone, she still may not be able to ask for help. Then might be when she most needs a friend.

See the dilemma? Usually I'd say sure, talk to her. But her being a therapist & your being her last remaining friend ... I'm not sure.

Big help I am. Sorry.