It looks fairly straight forward, they essentially aren't convinced about the strength of your relationship based on the information you provided. There is a lot of information on the Border Agency website which can advise you what you should send in, and you could submit this evidence in an appeal. Without wanting to seem rude, and whilst I understand the whole visa procedure is quite complicated, it seems you haven't really prepared fully for this and I think both you and your fiance need to spend some more time getting together the right information and going through the guidance on the border agency website.
Essentially, they have to make a decision based on the information you have provided. Try to flip the coin, and think if you'd been handed the information given and had to decide whether to issue the visa based on the evidence, would you have issued it to yourself?
Don't worry too much about your employment situation, unless it is absolutely necessary that you work in the UK for financial purposes. You can however explain that you'll complete the relevent food hygiene qualifications on arrival in the UK (though in fact you can do these online as well for a fairly low cost).
I wish you all the best, and I recommend you go through the evidence again with your fiance and decide what documents you need to submit. If you have a genuine strong relationship, this will show through in a good set of evidence and you'll have no problems in applying again or an appeal.
