The answer to the question of the right decision is that only the two of you (you and your husband) can decide together after an honest and revealing discussion.
Sexual infidelity is often not what causes couples to divorce but emotional disconnection, so it is vital to determine the facts before making decisions. Sometimes, a passing affair or a random fling is not a sufficient reason to end a successful marriage. On the other hand, long and emotional relationships with another partner certainly hurt the sense of trust and mutual love. Despite the difficulty, there is no choice but to have an open and honest conversation. Your husband's response has great significance. If he expresses a sincere and genuine apology, it is a consideration. Sometimes, it is advisable and worthwhile to seek the help of an objective factor whose judgment you trust, preferably one who knows both of you.
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