If I'm following this correctly, you're saying that you don't like going out with your friends because they're all drinking, and you're straightedge.
Just because you don't want to drink, or do drugs doesn't mean that you cannot go out and have some fun. You can just explain to them that you don't have any interest in having a drink or becoming intoxicated but would like to hang out instead. If for whatever reason you're uncomfortable or don't want to explain that you're straightedge - why don't you offer to be the Designated Driver for the night out? By being DD any pressure they may be putting on you to do anything will be eliminated, and you could be stopping them all from driving.
Being straightedge is nothing to be ashamed of, and there are many pros attached to it.
By being so - you are a reliable ride and you can save lives by not letting your friends drive while intoxicated.
It's nothing to be fed up, or embarrassed or anything about other than proud

& quite frankly, if your friends don't understand your views on not wanting to do anything and if they pressure you, then they aren't real friends and you can find others who will support your decisions