Either you have lost it or you haven't?but are you honest about it?
Many people tend to brag to their mates over their nightly exploits, how many people they have shagged and that they are out on the pull and "up for it" - the letter is probably the most truthful part!
Human nature means we exaggerate all our experiences, to gain attention and make us feel good. Unfortunately that can make others feel inadequate, but do bear in mind its usually just a popular topic of conversation for most.
It also does not always mean the person is fibbing - they really could be a sex god! By all means its ok to be promiscuous, as long as you are both safe and happy with the situation - and its equally fine to abstain from sex till the right person comes along - or to be super-picky!
So remember, even if your mates are at it constantly (or not), that does not mean you have to follow suit - remember its your body, your future?your decision.