Should I stop TTC? I'm 38 and almost 39.

Mag
Hello, I have had the pleasure of reading many of your journies in the TTC world and I have to say it makes me feel better to not be alone.
I had 2 miscarriages into 20's and then had my daughter only third pregnancy. Yes, I'm so thankful for her.
Well that marriage lasted a short while and I have always longed to have another baby if I ever got married again. I wasn't lucky enough to find my now husband until a couple years ago. Last year in December I had a MMC at 8 weeks (I was 37).  We had heard the heart beat already too. Anyhow, since last feb we have been trying. A couple months my cycles were odd but all in all pretty normal. I have been a total lunatic about vitamins and anything that could help my fertility. I even go to acupuncture. My doc doesn't think there is anything wrong w me other than possible low progesterone. 
I had the blood tests and antibody tests - all normal. 
Anyhow, this past December I had started testing early for pregnancy and had many positive tests several days before AF. I went to the doc to get blood tests and they showed the hcg declining and to be an early MC or chemical pregnancy. 
Anyhow, I'm just feeling very discouraged and that I'm a fool to continue this road of TTC. I want nothing more than to have a baby w my husband. I'm just so scared that maybe my time is up or it's not meant to be! I guess I'm at this point of do I keep going or not? Is there hope? 
I'm venting here and I have no one to talk to. I can't discuss this with friends as they don't understand. They will just say u have one child already and u should be happy.
Please, anyone out there reading this, any advice is appreciated!!! 
Thanks