TTC for about 10 years now.

I was married when I was 20 years old and TTC for about 6 years. I saw infertility doctors, took <a href="https://glowing.com/glow-fertility-program">fertility medications</a> and had several tests done. I had my tubes dyed to see if they were blocked and multiple blood tests and nothing seemed to work. Needless to say but my marriage ended because he wanted to have children and the doctors couldn't figure out what was wrong with me. They said I ovulate and I have always had normal periods. 
I also ended up having a lot of medical issues and was in and out of the hospital for years before they even knew what all was wrong. Since being diagnosed with multiple different things and my marriage ending I was in another relationship. I ended up getting really sick and they admitted to the hospital while I was there they tested my blood and said I was pregnant. I was so sick from my other medical illnesses that I never really had time to think. They tested my blood everyday and after the second or third day the dr informed me it was a molar pregnancy and I was devestated. 
I am now 35 and have been with my fiancé for about 3 and a half years. We have known each other since we were 11 years old. He is truly my best friend. He has a daughter that is 17 but he went thru a nasty divorce and custody battle and hasn't been close to his daughter for about 8 years   I know even though he doesn't say it that he wants more children and I have always wanted children. I feel like a failure because I haven't been able to have children and as a woman I feel like it is something I should be able to do. 
On October 30th I had a miscarriage and it was heartbreaking. I just kept playing it over and over in my head wondering what I did wrong. 
My OBGyN wants to refer me to a fertility doctor again like I had when I was married but my insurance will not cover any of it. My fiancé insurance will cover some of the testing but beyond that I would have to pay out of pocket and I'm sure you all know all of that can be very costly. 
I guess my question is.......is there anyone out there that has had or is having some of the same problems? I am looking for that last little bit of hope and faith in all of this. So any sort of advice or just someone to talk foto help restore my faith and hope at this time would be greatly appreciated. 
To all of you TTC you are in my prayers. And I wish nothing but the best for all of you.