Marriages fail for a number of reasons. From getting married too soon and not having time to learn about each other to living with a workaholic who is never home, maintaining a successful marriage is a challenge. When a married man is falling for someone else, it could be that he seeks attention, control or has an array of other needs. No matter his reason for exploring feelings for someone other than his wife, you'll usually encounter some signs, both subtle and blatant, that his heart is venturing elsewhere.
He Rushes You off the Phone
Pay attention when time he used to spend checking on you morning, noon and night is now devoted to some new activity. When he no longer feels the need to fill his down time chatting with you while on his way to a meeting or running errands at the grocery store, he may be using that time chatting it up with someone new.
You're Not on the Invited List
When you notice that you are getting fewer invites to go to his company functions or even to hang out casually with his friends on the weekend, his free time may be being spent elsewhere. Consider the change in his interest in having you around all the time.
His Stories Don't Add Up
He's lying to you and you know it; perhaps they are little white lies that don't make sense. Slowly but surely, he's telling more stories to cover up the others, and they are so jumbled you wonder if he's leading another life. From saying he's leaving to go help a friend but you bump into that friend at the store to him not answering the phone around you, something doesn't sit right with the situation.
He Hasn't Vented In Weeks
Sure, you're used to being the one who spills the details of your bad days at work to him for hours on end, but you're also used to him telling you about the crazy things that happen to him. When you notice a shift in your friendship bond and the way you communicate, he could very well be telling his new interest all the gory details, leaving him with nothing else to say to you.
He's Not Excited Around You Anymore
When his once-cheerful mood now seems lackluster around you, it's possible that all of his loving energy is being given to the new girl. The excitement of a new relationship can make him so giddy around her that he has nothing left to give you. If he's spent hours hearing from her how great he is, once he comes home, conversation with you may seem dull or rote.