Hi user, I'm sorry you're having these distressing symptoms, it must be really worrying for you. Have you spoken to your GP about it? if not, that would be the first thing to do, just to rule out any physical cause to what you're experiencing.
Also, have you had any therapy since leaving the bad relationship? Counselling to talk through what you've been through, or CBT to deal with the anxiety could really help.
When we're anxious our 'fight or flight' system kicks in. This kicks off with a massive surge of adrenaline which leaves us kind of like a coiled spring; highly emotionally and physically aroused and ready to pounce. It can lead to tingling or numbness in extremities, usually fingers, toes and face. The fact that it doesn't happen when you're distracted does seem to point to something related to thinking processes, but get this checked out.
The other thing that happens in health anxiety, is that we become super aware of every physical sensation in our body and we start noticing things we wouldn't have ordinarily. And if you're really looking for sensations in your body, you can find them. For example, if I say can you find an itch on your body somewhere, I bet you could find one, just because I've told you to think about it!
So, yes, it could be related to your anxiety, but you need to talk about it with your GP.