I don't know how long ago you posted this, but I read it and literally felt like I was reading something I had written about myself.
I am a 36 year old female and I have lost count of the number of people I have messed around by saying I can't see them anymore (because the anxiety has become unbearable) and then a few days later recontacted (because the anxiety has lifted by 'getting out').
I literally have that instinctual thought process of is this person 'the one' pretty much by date 2, then the anxiety sets in and the rest becomes a pointless attempt to battle the anxiety and not let it get to me, until I am so wrecked/exhausted and feeling almost suicidally depressed.