I am very glad that your T handled it so well when you told her you were masturbating during the session. If you can’t control it you shouldn’t be punished or made to feel bad about it after all I assume that is part of why you are seeing T. I find it a little troublesome that your T is encouraging it though. I am very dissociative. T understand that I get very dissociative during sessions and don’t always realize it yet alone have the ability to do something different. T is supportive when it happens and in dealing with the aftermath of my dissociation. T does not, even in these times, encourage me to use dissociation as a coping technique. He reminds me to try and keep my anxiety and strong emotions below a 5 on a scale we have worked out. He reminds me to do self care. He gives me space to talk about the things that are causing stress.
I can understand under the current significantly higher stress and phone or video sessions it is a lot harder to control the need to masturbate. It doesn’t sound like it is a sexual thing towards your T. It sounds like you are self soothing and having the unusual opportunity to have both sources of calming. Perhaps in these times your T is choosing not to focus on the PGAD. That bothers me a little because the more we allow any behavior that becomes troublesome the more we reinforce those nuropathways making it harder to stop later. I didn’t get the impression that your T was in any way participating, or even aware of it beyond your telling them. I also didn’t get the impression they were turned on by it or getting something out of it. So I would lean towards perhaps it not being best practice but not going so far as to say it was unethical.
Personally I would try to refrain from doing it in session on the phone/video just as you would face to face. I wouldn’t be hard on myself if it happened though.