Dude, seriously, props on getting married at 21. I mean this with all admiration, especially these days where many people continue their education into late twenties and might not even begin to think about a family until their thirties, but that has got to be rough. And what you probably missed out on, having evacuated from the dating scene early, is that under-20-year-olds are absolutely no end of frustration romantically or sexually once you've had any degree of experience yourself, and with that realization they tend drop in appeal like an orbital re-entry vehicle pretty quick.
I assume (I would direly hope) that you got married for reasons more than just physical/sexual attraction, and that despite current hiccups in the line there are enough reasons to weather a rough spell until, not having gone through the process I don't even know how long, but guessing at the demand of having a newborn, maybe a year? has passed. Whatever the case, remember the reasons why you married and love your wife, appreciate the fact that she made a goddamn living human person for you, and realize that it's a normal deal to want young attractive ladies to suffice your instinctual drives, but that we live in a time where you're going to have to get on the internet and deal with it the lonely way until your wife is good and ready again. At which point it will dawn on you that despite whatever internal conflict you might have right now there's never going to be anyone who is as deserving or worthy or effortlessly beautiful as the woman who mothered your son and you would likely regret it for the rest of your living days if you couldn't keep it zipped up and be a faithful and honest father when it's least convenient but the most telling of your character and mettle to do so.