I feel broken and so disappointed

Yesterday I found out that my best friend is pregnant. She is beautiful, wonderful, and going to be the best mom. Being a mom is something she’s wanted for a long time. I’m over the moon happy and excited for her, but I’m having a really hard time accepting that it hasn’t happened for me yet. I’m going on 2 years of TTC and she got pregnant without trying. She wanted to wait until after her wedding which was last month to start trying, but got pregnant by accident 2 months before her wedding. I guess I’m having a hard time because she is married to my cousin, with whom I’m also extremely close with. He and I are the same age and grew up together. Even as kids, we talked about how cool it would be if we both had kids at the same time when we grew up and how they could also grow up and go to school together the way we did. Now he and my best friend are expecting their first, meanwhile my husband and I are starting IUI in November after unexplained infertility for the last 2 years. I’ve had other friends announce their pregnancies and I’ve coped just fine. But this time is hitting me in a really deep place and I’m struggling a lot. My husband is beyond supportive, and my cousin and best friend are fully aware of the fertility struggles we’ve been going through. They are so kind and supportive of us and understand that it’s hard for us. I’m sorry for the long rant, I just needed to get it out. I’m so happy for them, but find myself asking why it can’t be me. I so badly wanted to raise our children together and not knowing if I’ll be able to have that is hitting in a really deep way. Thank you for listening