How do I start wanting anything again?

You didn't mention what happened, just that she needs "space".

It obviously takes two people for the relationship to work out.

What happened that led her to say she needs space ?

Also, if she was the "one" then why didn't you marry her ? Why did it take 4 + years and no proposal ?

You need to sit and think about everything that happened and her behavior and yours, NOTHING happens overnight. She must have been wanting to end things or have a change for some time, you were just not paying attention so you didn't spot it until she left. Ask yourself where YOU went wrong, she didn't leave, she just wants some space am assuming to think about you guys, or is there another guy in the picture ?

You say you have mostly gone with her plans.... Yikes, total pushover. You are the man, you need to take charge, women don't like a pansy pushover with no initiation in life.

You were just "there" without taking charge, without proposing after years of going out...

You have probably a year of super intense pain to deal with and then things will get better. If they don't, seek counseling. Good luck.

Stop feeling so sorry for yourself and start pulling yourself together; everyone goes through this atone time or another. This is just childish self indulgent behavior and will only get worse if you keep on giving in to yourself. Find a club to join, volunteer your time somewhere, be useful, try hospitals, nursing homes, museums, zoos, anything but start focusing on others rather than yourself.

Nah, if she was 'the one', she'd still be there. Drink up, mate. Time for the old liver to earn its keep!

If you want anything in life, just don't marry a woman. You will have enough money to buy anything you want.

Cheap booze and cheaper women always worked for me.

You can find some great advice from men who have been in your shoes here

http://www.mgtow.com/

you can do it by growing the hell up, you hypocritical baby.