They are there when we're being grumpy, mopey cows. And they are by our sides when we're vomiting/crying/running down the street after a night out.
Without them, most of us would be nothing.
But when you really think about it, being popular and having loads of pals does cost a pretty penny.
Amigo Loans claim to have totted up the total cost of friendship over an average lifetime - £142,118.
Apparently, we spend an average £68.25 (and the rest!) every month on socialising with friends.
According to those they questioned, women spend £60.59, whilst men spend an average of £76.21 per month.
Each month, we apparently splash out more than £30 on buying drinks for our besties, doing them favours or lending them items we never receive back - adding up to £392 a year.
As well as general socialising, over the course of a year Brits attend an average of one stag or hen do - with an average cost of £250, one wedding (£377), one holiday with friends (£400), two birthday drinking sessions (£80), one leaving do (£20).
Not to mention one children's party (£30). This all adds up to £1,157 a year.
Kelly Davies from Amigo Loans said: "Despite the true cost of friendship costing quite a bit, the memories and experiences you share with your friends of course outweighs the financial cost. Overall we are very generous when it comes to friendship, whether that be going for a coffee or a big life event. It seems friendship, to most Brits, is worth the money."
We don't care how much our friends cost us, we couldn't live without them. Mwah!
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