What are some signs that a therapist may have poor boundaries with their clients?

Routinely going over the time limit with certain patients, compromising the time for the next client.

Disclosing feelings, fantasies, and experiences to the client in ways not related to the work the client is engaged in.

Failing to mention the client in supervision/consultation, out of fear the supervisor/consultant will advise return to ordinary healthy boundaries.

What are "demonic attacks" and how can one tell when they're happening to them, or someone else? How would one go about dealing with it?

Sense of competition with persons who are important in the client’s life.

These items can happen fleetingly, briefly, in any therapy, but if they’re frequent, it’s definitely time for the therapist to get some good, solid supervision/consultation.

Session-expressed curiosities about client details not relevant to the therapy.

Ive been pretending to be okay and acting as normal as possible, but Im actually completely heartbroken after a recent breakup. Its painful and really affecting me, to the point where I cant concentrate at work, Ive lost my appetite, I cant sleep, and It feels as if my whole world has been turned upside down. I loved him so much. He said so many cruel things to me and it made me realize he must not have loved me the way I loved him, or he wouldnt have said such horrible things. How do I handle the heartbreak and why cant I accept that he didnt love me and just forget about him?

Obsessing about clients outside of work hours.

General Introduction to Boundaries from Panahi Counseling:

Eager anticipation (or anxious anticipation) of the next session in ways that distract.

Would you let your partner cheat on you every now and again?

Off the top of my ancient head:

Frequent phoning or texting of clients to “check up on them and make sure they’re OK.”

Struggling with fantasies of deeper connections with clients, whether sexual or parental or other intense or intimate relationships beyond psychotherapy.

Why do foolish atheists think their strange delusional theories are facts?

Serious disappointment when the client cancels a session.