How am I supposed to cope...Can you help me?

This is probably one of the most difficult things I've ever had to admit to and its something that I never thought I'd have the courage to say let alone accept.

I'm really not coping at the moment.

On Xmas eve my fiancee left me and my whole world basically fell apart. We were supposed to be getting married on October 2nd this year-the venues, honeymoon, photographer, caterers, DJ were booked and I had found my wedding dress.
We'd talked about trying for a family a year or so after the wedding, we knew where we were going and I thought we were happy. Turns out it was only me that was happy, he wasn't sure it was what he wanted anymore or if he loved me.
Christmas day and boxing day passed in a blur-I slept alot, I didn't eat and I didn't really talk, I cried a little bit but not properly(I cried the first few days but after that I decided I needed to pull myself together-I don't like to seem weak)
The day after boxing day my parents went to visit family and I went home to help him move the rest of his stuff out, not too sure why I helped him-I think i was still in shock-I wanted to see him for a bit longer.
The next day I went away with my parents and sister to see my Uncle in Holland for the week between Christmas and New Years, mainly because I couldn't stand the idea of being in the house on my own and not being near my parents and also because I just wanted to be away from everything. I didn't want to have to answer peoples questions or even begin to think about how I was going to afford the house and the car on my own.

I started this blog on New Years day, if you go back and read my first post you can see the kind of frame of mind I was in, I was excited about starting a new chapter in my life and becoming a new person, being away from the situation and home made it seem so much simpler, it felt like it was just a case of getting back home and going full steam ahead into a new life.
I'd deal with it, I'd cope and I'd be fine.

Problem is I've not dealt with whats happened, I've thrown myself into projects and anything I can think of to try and distract myself from the fact that things aren't ok. I've been putting on a front for the past few months and trying my hardest to not let people see that things are getting to me or affecting me.

The past two months have gone past in a blur, I cant remember what I did yesterday let alone last week. I've not slept or eaten properly in weeks and its really starting to take its toll, I wake up feeling headachey and dizzy, anything I eat makes me feel sick-clothes are hanging off of me (I've lost enough weight to go down a shoe size!) I haven't done any housework since January-luckily my sister has moved in and has taken over the main job of cleaning-my office and bedroom are a mess and I can't concentrate or relax when things aren't organised or neat. I manage best when there are routines and plans set in place, I like to know what has to be done when-it helps me to feel in control.

I'm in self destruct mode, I know I'm making myself ill, I'm contemplating silly things (like dosing myself up on the stupidly strong painkillers the Dr gave me because I know they help me relax to the point that I'm not safe to drive) I know I'm working to much, some days I feel nothing and other my minds going at a mile a minute and I feel like I'm going crazy.

I know I've been running away from things but its because I cant even begin to understand how I'm supposed to cope with all of this and all of a sudden over the past few days I've realised just how bad I've let it get.

So there, I've admitted it. I can't cope and I'm scared and most of all I don't know how to fix it.

I was going to wait until tomorrow morning to post this, I was going to sleep on it and see how I feel in the morning but I'm worried that if I don't post it now I'll convince myself I'm fine and carry on again for another few weeks and make it even worse.
Strangely enough at this moment in time I don't feel scared putting this out there for all to see, at least if my feelings are out there and written down I've admitted how I'm feeling, I realise I'm making myself extremely vulnerable by doing this but I wouldn't be doing it if I didn't think I needed too, in all honesty I'm scared about how things will carry on if I don't.

So this is me reaching out, I'm asking for help, how do I go about tackling all of this?
Where do I start?