Heartbroken and ready to quit

My ex-husband and I tried for my daughter (almost 7 now) for almost 10 months. I eventually gave up and found myself pregnant the next month. We decided to try for baby number 2 before our relationship deteriorated. That went on for 2 and a half years. We both had fertility workus, I had an hsg done as well as some lab work. Found out my hormones were extremely messed up. Most were all 3 to 5 times higher than they should have been. It hurt to hear that as they had no recommendations for a fix. My periods were severely irregular then (showing up once every 6 to 10 months and lasting for about 2 weeks on average). I have since lost about 20 pounds and my periods have dropped to every 27 to 31 days (there have been 2 cycles this year that were 40 days) so I am wondering if maybe the hormones have regulated themselves. My fiance and I want one child together and it has been so frustrating this past year and a half that nothing has worked for us :( I sometimes feel like I am going to go nuts and my friends are all having babies like its nothing, they can get pregnant when they want to. They want me to be happy for them and it is so hard to smile and say well congrats again.