Unless you or the wife was under the age of marriage (18 in WA), how old each of you was is not relevant to whether your marriage is valid. There is no law in WA that would, for example, prohibit a 60-year-old woman from marrying a 20-year-old man if they are eligible to marry and want to marry each other.
"i do not know if i can stop the prosecution". I do not understand what you mean by "prosecution" in that sentence.
If you no longer want to be married, you can file a petition to dissolve your marriage.
You should review the specific facts with your attorney to find out what your legal options may be.
So you seriously didn't know how old the woman you were marrying was? Fraud generally makes the contract voidable. This means the marriage contract is valid unless you take the necessary steps for an annulment.