Have you explored in therapy what your childhood bonding with your parents was like?

A relationship with a therapist can feel quite tricky. It's a professional relationship, so you pay money and then the therapist offers almost unconditional attention, empathy, listening, etc.

So if you are a client who didn't feel unconditionally loved and cared for by your parents as a child, and you have a deep craving for that type of love as an adult (that you didn't get as a child), therapy can provide a sort of simulation of that love.

But it's important that that simulation be used for healing and to move forward. From your post, you have been seeing your T for at least 3 years, yet you have still not delved into this core problem, which makes me wonder if your T is not doing the best job.

It's also very common for adults to confuse a need for parental love with romantic love. This is why child abuse victims can easily wind up with lovers as adults who also abuse them. The endless quest to re-do childhood and have a happy, healthier ending, even though unfortunately it typically just leads to repeating the abuse cycle over and over.

But because it is so common for people with wounds and dysfunctions from childhood to seek out (subconsciously) parental figures in lovers as adults, I don't think there is anything bizarre about having romantic feelings for a T, if a client has that problem, and the T is providing a paid simulation of parental love.

But again I think it's concerning that it's been 3+ years in therapy and this fundamental issue hasn't been addressed yet. When a T doesn't really do their job but rather just panders to the client, then it becomes more like paying for the emotional equivalent of an escort, which can make romantic confusion issues even worse.

I would also advise being single until you figure things out. Cheating on people puts their physical health and emotional health at grave risk. You can't mend hearts you break, and you can't take back herpes.