Stay At Home Mom

Is it normal to feel lonely as a SAHM?

Honestly since I had my son (17 months old) I lost pretty much all of my non mom friends and I have yet to be able to make actual mom friends that aren't working moms or have children much older than my son. It sucks some times because I feel like I have no one to talk to other Than my son and SO. I envy the other woman that are out at the playground with all of their children talking and laughing. Their little ones are all playing together and have lots of social interaction. All the while I'm watching my son play by himself and worry if it's my fault the reason he doesn't talk much. It sucks so much to feel this way sometimes but I don't know what to do. I've tried getting out there but I've yet to find a true mom friend that I can just talk to and enjoy their company. Is