W-- or, I suppose, STBX-- is not still in my life. She moved out on April 1, and since then we connected once to share closing thoughts (my "friends don't traumatize friends" speechifyin') and again for me to tell her how to get the D papers. After I turned down her overtures of friendliness, there has been zero contact, and I expect that will continue.
TenBook, I don't know if I can suggest meaningful advice, exactly, but I can tell you what strategies I'm using. It helps immeasurably that she has moved out. If she were still "living here" (I put that in quotes because, as I think mentioned, she only spent 4 of the 33 days prior to moveout actually here, with the other 29 using OM's place as home) then I am sure it would be nigh-impossible to avoid that broken, defeated feeling, because I would be (and was) constantly reminded of her abandonment of the place where she belonged. But because she is gone, and I have completely removed even the smallest suggestion of her-- all her belongings, all the art she acquired, even the kitchen utensils that she used and I didn't-- and because I have unfriended her on Facebook, the only thoughts I have of her are the ones that I allow myself to think, and not the ones that are forced on me.
And when I keep myself busy, I don't think about her. This was in fact a marital problem when she was here. She needed Quality Time to feel loved, and I was constantly working on some project or another. I have no shortage of activities to keep myself busy, whether here or at home. I have three scientific manuscripts that need to be finished, a new book to write, audiobooks to record, two books to revise, two theater projects to work on, a film audition to produce, acting classes to teach, an apartment to clean up, and (of course) a job to hunt for. And that's just all the stuff I can do here at home. Once I look outward at the activities I could participate in, and the places I could go (even just by myself), it's pretty obvious that I could be busy pretty much 24/7 if I wanted to. And I know for certain that keeping myself busy in those ways feeds my ego and keeps me happy.
Which means that if I find myself idle, feeling broken and defeated, depressed about her having a great time and exciting sex with OM, I remind myself that I am choosing to succumb to these feelings. There's no denying that it's the worst hurt ever (I understand now why the Bible makes moral equivalence between adultery and murder), and I have no shortage of complaints about her awful behavior and moral failure, but that battle is lost. She is gone. And I've got work to do.