<human>: Male coworker/friend [24] of a couple of years gave me [26f] quite a bit of money as a gift for my birthday. Is it appropriate for my friend to give me so much? (It was like 60 bucks, which is awesome, but really seems like too much.)
What should I say? Should I tell him that it was too much? Should I give it back? Should I buy something yummy for the office with it? 
How do I bring this up with friend? 

(I was the person who organized the party we had for him in the office on his bday. I also made cupcakes so I guess I did something nice for his bday too? It's not insanely out of the blue in that regard.)

I'm not sure if relevent, but I've also been in a relationship for 3 years with my boyfriend. Is it weirder that my guy friend is giving me a big present (in the sense that I'm not single and maybe that's innapproriate?  My bf doesn't care, he thinks if he's willing to give me such a big gift than whatever?)

Can you give me the gist of the text in a nutshell?
<bot>: How much is too much for an opposite sex coworker/friend to give as a present? How should I broach subject with friend?