Very big hugs to you. Endings are never easy, but it does make you stronger in the end. We never want these things to happen, these horrible endings to what was supposed to be happily ever after, but there is always a reason for it.
When my 8 year relationship with my former fiance ended in a truly crappy way, I thought the world ended. At the time I couldn't imagine ever smiling again. I later learned he wasn't the one and that I was going to be able to love again, laugh again, and although it took time, it happened. As was mentioned above, it wasn't time wasted. Those years helped shape me into who I am today. I learned a lot about myself, about what I want and didn't want. Despite the crappy end, I still cherish so many memories from those 8 years.
Be easy on yourself, take time to grieve, but always look forward. Don't let this stop you in your tracks, but make baby steps forward, even if it feels like one step forward and two steps back for a while.