Warning: If you are a dedicated GSR fan- this story is most certainly NOT for you. Read on at your own risk.

I was listening to the radio and the song "Unfaithful" by Rihanna came on and inspired me.

(Alongside personal experience of watching a long distance relationship simply just dissolving in the matter of a year)

I hope you can understand where this is coming from. Please review.

Also thanks to Charlie for the encouragement on this one.

Disclaimer: I own zilch.

The Reason that the Sky is Blue

Part One: Grissom

The evening had come and gone as the night settled in with all of its intensity over Las Vegas. The darkness acted as the perfect cloak for sin. The fireplace crackled beside him as Gil Grissom sat hoping that the taste of Jim Beam would cure the ache that had settled in his chest. He laughed inwardly at just how appalling his method of avoidance was but acknowledged that nothing else would have suited the turmoil that had cast itself like fog over his life.

It was the click of the lock that brought everything back down to the same crashing reality that seemed to plague him. Sara appeared through the door her coat wrapped firmly around her waist and held shut to hide what she was wearing underneath, the make-up she wore was more than he had ever seen her in before. Her expression was that of guilt- a look that he had almost memorised over the past few months. Grissom looked away not wanting to catch her eye as the sound of her heels neared him. He knew that if they exchanged an honest look the facade they had built around their hearts would come crashing down.

"I'm sorry I got caught up at work." The words came out as a raspy, whisper.

He could feel his heart stop as he swallowed another one of the lies she had prepared for him. He had gotten used to simply just giving her a half smile pretending that he couldn't see the obvious finger prints of another man across her skin, her heart.

As time had passed it had become obvious that her disappearances for hours at a time were for secret rendezvous. She'd changed. The things that he had memorised about her behaviour had slowly dissolved. There were things that Sara now did that Grissom didn't recognise as the actions of his wife. She'd started wearing her wedding ring on a chain when she went out, a chain he presumed she would take off and leave on the night stand of the man she was sleeping with. He'd picture the gold glinting in dim lighting as her new found attention to her appearance was praised without words. He'd caught her deleting messages from her phone- something she had never done before unless the inbox was full. And the most of obvious of all changes, the fact she appeared to be constantly nervous around him. She would flinch as if his touch burned when he'd embrace her while they were in bed. She'd close her eyes for the few seconds it took to say "I love you".

His heart had become like a battlefield as he warred with himself over what was the right thing to do. He would look at her completely lost in intensity of the love he had once felt for her and like a ghost choose to remain silent over the issue that was tearing him apart. Grissom didn't realise how much it would hurt knowing until he had to watch her walk out of the front door every day knowing that there was a chance that she would be with him. It was like a knife to the gut when she would reappear in the evening with a 'sorry' that was layered with remorse.

But every day for the past three months he had accepted that it was a way of living. It was a way of not completely losing her.

In as much time he had figured out who it was that seemed to be slowly tearing his wife's heart away from him; Greg Sanders. A friend. A solace. A companion. A younger man, with charm and a disarming smile.

Younger.

That was something that bothered him, or rather, worried him. His very obviously increasing age had, had an impact on their bedroom activities and his grown to be more aware of his changing form while his wife had maintained all of the signatures of youth. Their age gap had always worried him but they had connected on such a deep level that the physical aspect of their relationship hadn't seemed all that important. It was not until now, where he'd attempt to force images of Greg and Sara out of his mind that he realised just how much of an impact it truly made. He thought of the younger man satisfying his wife in ways he hadn't been able to.

But knowing that it was someone who genuinely loved her made it even more painful. Because it wasn't just about sex. Greg was not simply a man she had used to forget him, their problems and then tossed aside. No. There was so much more to this. He was someone that made her feel safe and cared for. He was a close friend, someone she genuinely trusted to not hurt her.

In his mind he would imagine Greg taking advantage of Sara's vulnerable state; he would have pulled her closer while she cried on his shoulder, his hands carelessly rubbing her back and leg as he attempted to comfort her. The feeling of her body pressed up against his too much to ignore, Grissom could picture the way he would drop his lips to hers ignoring her initial resistance. But no matter how hard he tried to convince himself of the story he realised that he couldn't. Greg had stood aside for years, he had simply let Sara have what made her happy, and as much as Grissom wanted to believe it, he couldn't imagine the younger man acting inappropriately with her after all of this time.

That theory was pushed to the back of his mind and another would reappear. It was this hypothesis that ripped through his heart like broken glass- Sara had instigated their affair. She'd just wanted to the hurting to stop and silence her doubtful mind as she led him by the hand to his bed silently inviting him to make love to her.

It was the knowledge that there was something that Greg could offer her that he could not, there was something that he wasn't doing that destroyed him as he sat pretending to believe Sara when she said that she had been working late.

Grissom realised that perhaps he didn't want to confront her for the fear of losing her completely. He was worried that if he asked her to decide, she would choose Greg.

He realised that he wouldn't be able to cope without her, so perhaps remaining quiet over the issue was all he could do.

Perhaps hoping that she would return home to him at the end of the day was all that was left.