@Mo38,
Rather than take peoples opinion on something you may not be expressing well, do an internet search on 'Signs of cheating'.
You will find numerous sites that list all the signs. Many sites will also explain why those signs (as a whole) indicate unfaithfulness. You can go through the lists and see how many signs are ticked off in your situation.
Other than that - if it of any help at all - given how you explained your situation, I think you already know the answer to your question.
Quote:Am I over imagining this or could she be seeing someone else and is throwing 14 years down the drain.
Given what you're describing, this likely isn't a fair question regarding your wife.
Your euphemism though, lends itself to the analogy: without even realising it, sometimes things can trickle slowly down a drain until they are all but gone. (ie. the question may not be fair to your wife, because the counter question could be 'is there anything left to throw down the drain?').
The question for you may be 'is the remaining savable', or 'can it be refilled again', or even 'what do I want from here'...it's something that you need to work out within yourself. Counselling may help (either individual, or couple).
Best Wishes