You can probably annul the marriage. Not sure what to say about the kid though.
IF you can agree on all the settlement terms then divorce is cheap. If not, then it's going to cost a lot. Mine (married over 12 years, no kids) cost me over $5k in attorney fees, only to find out I still lost everything and pay an unbelievable amount in spousal support. But every case is different. Hope you guys can do it peacefully.