nieces, nephews TTC and depression

I'm so glad my brothers had children. I have been TTC for over 5 years. Had a miscarriage 6yrs ago. And boy when im in a crap mood does having them over just make my days better. Suffering from PTSD and depression, these little guys are like happy pills. I just hope that one day I'll get my chance at being a parent even though I am so depressed. I hope that maybe just having a baby will help me. that unconditional love.