My spouse and I were raised protestant and worship that way for over 20 years of marriage. My spouse has decided to pursue being catholic. There has been some influence by a family member that if we both don’t become catholic that my spouse should divorce me be cause our marriage is not recognized by the church.
That family member is incorrect. The only individuals who are required to be married in the Catholic Church are Catholics. Since you and your spouse were (presumably) baptized Protestants at that time of your marriage you are considered to be in a valid sacramental marriage. Even if your spouse converts to Catholicism, that won’t affect the status of your marriage.
Of course, you are most welcome to explore Catholicism with your spouse and determine if you too want to convert, but you are under no requirement to do so.