I think it is in our DNA to instinctively know when our guy is becoming distant, notwithstanding his repeated denials. Your mind begins the queue of wondering and worry takes root. First of all, calm down and try to figure out why he is pulling away.

While there is the possibility that he could be losing interest in the relationship, sometimes, the withdrawal may be to rethink and strategize so that they quit feeling like they have failed you.

Most women are quick to point fingers at cheating as the sole reason- but this is not always so. Don’t freak out, go into detective mode and nag him out the door faster. Simply let it sink through your actions that you are there to support him no matter the stuff he is going through and that you will be available to listen when he is ready to share and leave him be.

Try focusing on him and let him have his space. Focus on doing things that make you happy, especially the hobbies that are not tied to him. If you cannot cope with the distance, let him know how you are feeling without casting blames or judgment.

At the end of the day, one of three things will be the result. He will open his shell and come back to you, he will be open about the cause of the retreat or he will end the relationship.
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Well,it is important to find out why he is withdrawing. A woman should not rush to conclusion that he is seeing another lady. Be a detective and at the same time do not nag about why he is distant from you.