Squeaky - I feel for you, Man. A few things I've figured out on this topic:
They say "love makes you crazy" but heartbreak can make you psychotic. Your wheel of fortune now has the seven stages of grief on it and takes you for a spin hourly, daily, or weekly. Recognize these and understand what your are feeling.
Refuge in drugs and booze can help turn your life into a slow-motion train wreck leaving a deep and destructive crater when you finally hit bottom.
Avoid getting into anything you hope will be a serious relationship for about half as long as you were in the previous one. Rushing into someone's arms can really hurt a wonderful woman because you haven't worked through your pain and unburdened your emotional baggage.
Go see a therapist and truly spill it, open up, cry and rage and let it all out. If having a professional help guide you out of the place you're in seems expensive, it's a bargain compared to the costs of heavy drinking at the bar. Or wasting months or years of your emotional life trying to work through this solo. Or becoming bitter towards women while your heart shrivels into a dessicated leather knot.
Get out and stomp on the ground, exercise, do hard, honest work, read the classics, focus on something that gets you into the flow. Then grieve in your off time.
If what you felt was real love and you were emotionally invested in the relationship, don't even think of being "just friends." Delete her number and get on with your life. A few rare people are emotionally evolved enough to make that work. The rest of us primates are either getting our ego stroked having a puppy that comes over to help cook or move heavy furniture, or hoping deep down for a second chance if we're just in the right place at the right time. One's cruelty and the other's a tormented waste your precious time on this earth.
As it is to imagine right now, you'll get through this and one day you will laugh joyously from your belly until your cheeks are sore, bask in the company of true friends, thrill in the heights of a schoolboy's crush, and feel the comfort and bliss of being with someone you deeply love.
Good luck getting through this. My wish is that you emerge from this crucible a better, wiser, and more compassionate man capable of loving fully and with a wide-open heart.
Nothing in the world is more yielding and gentle than water. Yet it has no equal for conquering the resistant and tough. The flexible can overcome the unbending; the soft can overcome the hard. - Lao Tse