That looks like deterioration similar to what I've been experiencing lately. In fact, I just got rid of about half a dozen pairs because of it. Unless your shoes are full grain leather, I think this is bound to happen sooner or later, and I will venture to say that it will happen with increasing frequency over the next few years. You see, neither of us much like what is being offered these days style-wise, so we are pretty much stuck with older shoes. Unless those older shoes were particularly expensive, and sometimes even if they were, this is going to continue.
As far as the heel cap goes, I feel your pain. I wouldn't give you two cents for the heel caps on those hollow, plastic molded heels. I remember when me and the ex-wife were first married, she bought a pair of what I thought were expensive shoes at the time. Somewhat similar in heel height and style to your Cathy Jeans. Within a month, she had lost a heel cap, and I was horrified to see what that heel was actually made of--plastic. I didn't know all that much about shoes at the time.