These are but small ramblings I can offer. And these are assuming that there is no chance of a relationship recovery.
If it helps, blame her. Blame her for everything she has done to you, blame her for wasting two years of your life, blame her for doing this or not doing that, or even constantly leaving the toilet seat down. But blame her. It's a lot healthier then blaming yourself, trust me.
Don't do anything stupid. It's never worth it in the long run.
Find a new hobby. Something you've never done before. It will force your brain into problem solving mode and force you to use less energy on the grief. It's a nice way of tricking your body and you'll learn stuff in a new field as a bonus.
You've heard the expression that time heals all wounds. I know it's the last thing you want to hear at the moment, and that you want (in fact you actually need) time to be depressed, but take consolidation in the following fact. The human body physically can't remain depressed about the same thing for a consistent amount of time. It's not possible. So whether you like it or not, you will actually pull through. There's really nothing you can do about it.
As a rough guide it takes about half the time you spent with someone to get over them. So it will probably take you about a year. Roughly. Don't count the days. A year will fly by before you've known it.
Cry. Cry a lot. Scream into your pillow, thrash about in your sheets, and punch with all your force into the matres. Cry some more. Crying makes you feel good afterwards. It's why we do it.
Write her letters - but never give them to her. You'll be amazed at the weight that gets lifted by doing this.
Last, but certainly not least, trust me. The above is from personnel experience, and if you find a better way, for gods sake let me know.
There are people out there that care about you. In fact, some of them you haven't even met yet. My heart is with you.
