Second attempt at PhD
Yes, you must include it in your CV. Concealing it could result in all sorts of trouble later.

Your cover letter or statement of purpose should explain what went wrong last time and what will be different this time around. For example, you could discuss the job vs. studies uncertainty you had last time, contrasted with your current intention to retire and study heart and soul.

For the age concern, see How old is too old for a PhD?. In particular, I did my PhD after retirement, in my 50's, and have no regrets.