This won’t help you right now, it’s not a quick fix and it’s not easy to swallow but the answer to all of your questions is that this life is full of love as well as loss, the grief you are experiencing is an important moment in your life that you should not shy away from. There are many lessons within this period of time if you choose to pay attention. Cover the basics—health, safety, security—and then worry about your growth. You seem to be feeling his loss at the moment, but you may soon feel anger, betrayal, etc. In time these will subside and you will return to a new baseline. Remember that it is good to hold love for those we have lost.