Stop waiting, honestly just stop!!
At this point you are literally pushing the relationship down the road, and your pulling him with you....reluctantly!!
Is that what you really want? Someone who is with you reluctantly???
If he really truly wanted you, he would be contacting you willingly, he would initiate that contact, and her certainly wouldn’t have been texting some other woman, and breaking up with you.
Even if he is self sabotaging, sabotaging your relationship he is doing it quiet willingly.
The breaking up with you, the texting the other woman are all symptoms, symptoms of not being happy enough if his relationship with you. There isn’t always some huge argument, or some reason behind it sometimes people are just not happy or think they could be happier in a different relationship or alone.
As sad as you find this OP I would let this one go. He’s been unfaithful if only through text, he’s not exactly jumping up and down from rooftops to want to be with you, it’s basically all you have left is the habit of being in each other’s lives. You can do so much better than this!!!