You may be able to get some help through your local pro se office. Contact the clerk's office for the County in which your husband filed and see if they offer any services for financially qualified individuals. Regardless of your financial circumstances you should meet with an attorney to discuss your options.
I wish I could give you more information, but you need to have someone review your husband's counter-complaint with you to figure out exactly what he is claiming and why he chose to file a counter-complaint --and you need to do it quickly since your time to file an answer is running. Believe it or not, adultery is a misdemeanor in Maryland subject to whopping $10 fine. While the criminal element is often disregarded these days, there are serious implications involved in admitting to adultery as grounds for divorce.
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