Looks like its unsuccessful again :(

6 days to AF. I've started with the light brown spotting I get before every period. Still light cramps and low back pain. 
It's now 6 months we've been trying with no luck. We don't BD a lot due to time and stress but we make sure to do it every ovulation days (every day or every second day). We think I had a miscarriage on month 3 as my period was two days late and then extremely heavy (compared to others). 
When I was 28 I had a pill abortion due to an unwanted pregnancy (pls don't judge me) and now I can't seem to get one when I'm trying and desperate for it. 
I'm 33 (on 02/02) and loosing hope. I don't want to be an old mother who can't even run with her child and have one in my 50's after fertility treatments. 
I don't understand why it's not working. Drunk girls in bars get knocked up all the time, why is it so hard for me when I keep myself healthy?