It totally depends on your relationship with your present partner.painful episodes of past can be covered by happy thought of present

It depends on what kind of relationship you share with your current partner .how expressive you are and how mature the partner is to comprehend human issues.to discuss in detail connect with psychologist

Everything in life passes. In fact we feel life when the previous moment gives way to the next moment. Life exists in the here and now. Nothing that happened earlier will halt the flow of life into newer times and newer experiences. The past remains as memory, the present as the proof of existence and the future holds expectations, hopes, anticipation etc. So, my feeling is that having a new partner will help overcome the sense of loss about the old partner. Yet it will remain as a memory within your mind, probably for life. Such memories will stop hurting you when your relationship with the new partner is strong, mutually rewarding and based on mutual respect, with the passage of time..

New relationships need not bear the burden of previous relationships. The new relationship deserves  a fresh approach. It's important to develop a helpful perspective about previous relationships.