Fertility Issues? Need advice and to vent.

I met my fiance when I was just 10. I didn't know he was the love of my life then, but when we started reaching high school, we finally developed romantic feelings for one another. But like most high school relationships, we broke up for immature things. It just wasn't meant to be at that time.

I had moved on and fell in love with the man who would later, father my beautiful son, who I am so grateful for. But that also wasn't mean to be and unfortunately, I lost the man I loved, before my son was born. It was heartbreaking losing him and knowing my son would grow up with out his father. And it took my a while to regain hope that I would find love again.

Fast forward to 4 years later, I get invited out by a mutual friend to hang out with a group from high school days. I oblige, given being a single mother, I needed to get out and socialize again. And that's when I ran into my ex. 13 years later but still him. We started dating shortly after that and we've been together ever since. We got engaged and he's adopted my son. It's been a dream come true.

Last year, I was diagnosed with Non-Hodgkin Lymphoma which devastated us, as we were ready to start our family. I took an alternative treatment which was less aggressive, in hopes to not lose fertility. And after going into remission and getting tested, my doctors said I should be fine.

We've been trying since last October and have gotten pregnant twice but unfortunately miscarried both times. The first I had fallen down the stairs and I was close to 3 months. The second time was shortly after and I didn't even know at the time I was pregnant. But it wasn't any less heartbreaking. We want another baby so bad and I cried a lot when I found out . It's been months since and nothing. We're keeping track of ovulation, doing all the necessary things to get pregnant. But every month it keeps not happening.

I am scared that it might be me and because of treatment. I feel like a failure every time I get my period that I am unable to bring a baby into the world. It stresses me out and I can tell my heartache, is hurting my fiance as well. I don't want to make him feel worse but I just... Sometimes I can't help but cry when I see baby clothes or think about them. Am I alone feeling this emotional or others out there? I feel lost.