It's so nice that you are on Zoloft (sertraline), as this selective serotonin reuptake inhibitor (SSRI) is considered to be a very safe anti-depressant during pregnancy.
I hope that the 75 mg does the trick for you, but it is my understanding that many individuals require 100-150 mg to obtain good results.
If you decide to become pregnant again, take into account your own mental well being, and the effect that will play on the role of your developing infant. Women that suffer depressive/anxiety disorders that are not being treated during pregnancy, can harm their baby both during its development and in the long term too. Infants born to anxious/depressed mothers have a higher incidence of low birth weights, being born prematurely, and having impaired neurological development. Later effects include asthma, dyslexia and learning difficulties. They are also much more likely to develop anxiety/depressive disorders later in life.
The very best to you, Rose!... Chuck