.....There are kits you can purchase which detect even the slightest amounts of semen. So, if her soiled panties are showing semen, and you haven't had sex for a few days, then there is your proof. However,
not finding semen does not prove she's not cuckolding you, but simply that she's not allowing her lover to cum inside her. You can purchase those semen test kits in most ******* stores, and they are readily available on-line.
.....Next question, however: Let's suppose you DO find semen in her panties;
now what? Do you confront her with what you find, and what will be your direction should she admit it? This is not a game, and its no place to try to bluff your way through, because, if she's having sex with others, she'll most likely have sex with others again unless the reason she did have sex is corrected. In general, married women are less likely than married men to simply have sex with others
IF her life with her spouse is a good one ... married women tend to be less spontaneous about sex outside their marriage.
.....So, if she has cheated on you, you should do a self-evaluation to determine what might have changed with you since the two of you were happier, and attempt to correct whatever needed. Then, decide if the marriage is worth moving forward or getting out of ... simply confronting her with a semen test is only going to increase the friction, if there is any. If you can sit and talk it out ... great, if she avoids talking, time to bail. Sounds like, to me, she's fallen out of love with you.
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