when a male partner started to realize that the passion and attraction might not be existing in their relationship.

When a wife isn't enjoying sex, she had stopped doing all the things she did in past and this is the biggest sign your wife is not sexually attracted to you. 

she is not enjoying the physical intimacy, she stops sex halfway through asking you a question or telling you some story.

When your wife is not enjoying sex, she is encouraging you to finish because she isn’t having a good time and good mood.

When your wife is not enjoying sex, she is not reaching orgasm after doing sex and there is a possibility that something has shifted.

If your wife is not enjoying sex, she probably won’t be passionate, caring, or excited during sex and as a result you also not enjoying. sex anymore.

if your wife’s sometimes passivity but total passivity is a sign that she is not enjoying the sex you have.

She constantly changes the topic.

You feel that there is nothing to share with her because she is not like to listen to you about your feelings or emotions about emotional and physical intimacy.

She sleeps earlier than you.

When you both are going to bed at different times it indicates that she is not sexually attracted to you.