Can someone answer me these questions - who do we owe the deficit to and why do we need to pay it?
We owe the deficit, in a large part, because we buy more stuff from abroad than we sell.
In order to pay for that, the government sell "bonds" (gilts technically), which are a promise to pay a set rate of interest per year + all the money back at a certain date in the future.
These bonds are sold to foreign investors, mainly, in their currency so we get actual chinese yuan, or japanese yen, or US$ in return for them.
These are then used to pay for our imports.
Our deficit is thus how much the government owes, in bonds, to these individual investors.
The problem comes when .gov decides to issue more bonds to pay the interest, because we don't sell enough stuff abroad, or the economy doesn;t increase enough to cover the payments
DC is very fond of comparing it to household budgets where you're spending more than you're bringing in or the easy credit card comparison....except....hang on, can't we literally just print money? what household can do that? and the banks do it every single day literally create money (or, debt as it should be called) so how come the value of the pound doesn't drastically collapse?
Technically, .gov and the BofE don't print
money, they print currency.
And the reason it hasn't collapsed (yet), is because people believe in it - tinkerbell economics.
As soon as people start thinking "hold on - this fiver's worth bugger all, cos the government keep printing more and more", then we'll end up with a situation such as 1930's germany where the german bank (reichBank?) printed so much money it became worthless.
There is a story that a woman took a wheelbarrow full of reischmarks(?) to the shop to buy a loaf of bread.
Someone stole her wheelbarrow, and left the money behind.
And that was a 1st world country - and in living memory!
and if thats the case why are we even bothering to make horrendous cuts, tighten our belts "we're all in this together" bs when its all a big illusion? 
Because if we don't make the cuts, and .gov decides to carry on trying to print it's way out of trouble, people will stop buying our treasury bonds, and then we WILL be in the doo-doo, cos then all the foreign-owned companies will pull out of the UK, and the economy will collapse back to third-world agricultural.
It nearly happened in the 1930s USA during the great depression. Again, a 1st world country, again within living memory.
i think we're in danger of swallowing a big fat lie here 
Yep. But it's a lie we've been swallowing since the major currencies of the world were taken off the gold standard in 1971 and allowed to create as much as they liked, unchecked.