How should one go about getting closure if there has been no contact for an extended period of time?

in my experience with situations like these, I've had to create my own closure, taking my time to grieve the loss of the relationship, trying to move forward & heal. However, sometimes an opportunity for closure presents itself & in instances like those, I take it. We are not all granted the opportunity for closure, so my motto is if you are, please consider.
More on creating your own closure: https://www.youtube.com/watch?v=41rujD3fRBM