No we don't give up easily
Ok... firstly, is he not texting or calling you because you told him to leave you alone?
(sometimes men take that literally and don't realise we actually need them to call and say how much they love us, even when we tell them not to!)
Next, can you get him to come round?
As a first point (and I have been in this exact situation 2 years ago), I would get him to text or call her in front of you and explain very clearly, my wife has seen texts from you and is very hurt and upset. I do not wish to put her through any more pain. Therefore, we can no longer keep in touch. Please do not text or call me again.
You need to see/hear this for yourself before you can even think about moving on.
IMO - I'd get him to ring. I got my dh to text when this happened. It just meant she rang him later when I wasn't around to get an explanation and to hear it from him. If you hear them talk and end it there and then you have a tiny bit of comfort.
Could that be a first step for you?