I understand how you feel, but the advice given thus is sound.
You either live your life in the past, comparing any woman in your life - who will obviously fail - and being dissatisfied, or you learn to get a perspective on the situation.
Your love has gone, and the relationship you had with her has gone as well, and it is not coming back. Yes, you may pine for it, but you cannot allow it to poison the rest of your life - and that is what it is doing.
Make yourself invest time and emotion in your current - or next - remationship, and don't measure an innocent person who is going to fail without ever knowing why.
Your choice is to stay in the past, and avoid the possibility of a new love, or live in the present, with your past relationship firmly in its place - a memory, not a template for future relationships to fail by.
You have to make a decision, because living in the past is making you, and other, unhappy. Enjoy your memories, but keep in mind, that is what they are - memories.