Im not an ensecre and jealous person normally,been married 22 years,got at young age due to pragency,we had a?

falling out early in our marriage,we seperated for 7years and got back together,its been 10 years that ped now.we threw all bad memerios away and only remember the the good ones,it took some time to forgive him, he did gain back my trust.in the past 6months ive been getting these weary feelings as if my husband may have cheated on me recently,Why a sudden change of feelings all of a sudden ???