On the verge of giving up..

We have been trying for a year with more and more set backs every month. I know to many that doesn't seem like long. I'm 21 all of my friends are on their 2nd or 3rd child and I cannot get pregnant. We have been to fertility doctors and havw tried iui and injections. Nothing seems to be working.... the amount of money we have spent and mental strain it has our on me is insane. I wanna quit so bad but then it will never happen.