My condolences to you TT, losing family is never easy. The closer they are, the harder it becomes.
While cliche, times does heal the wounds. Try to remember the good times, and be happy for the person that, while taken from you, isn't suffering anymore. I have witnessed far too many slow miserable deaths of close family members, and so was happy for them when they finally found release.
This time is a mourning not just for those that died, but for those left behind to pick up the pieces. If you believe in the afterlife, then they will always be with you in spirit, and can derive comfort from that and be able to move on.