Yes!!!

However, if someone is in a "Convence" relationship: is it really cheating? Do both sides have to agree that it's a convence relationship to be one?

I once read that 80% of men cheat. That was years ago. I don't know what the percentages are now. And, if 80% of men cheat, who are the women they are cheating with? Are they cheating too? Some probably are.

Of course they do. Mutual consent.

Even if they have agreed to "don't ask, don't tell", which I really think is a sham.

Sadly, other people believe this too. However, the fact remains that you are not alone in your relationship. There is another caring, loving, vulnerable human being involved who trusts you and has faith in you. That most likely IS committed to you. Does it speak well of your character to betray their trust in you and to pretend to be someone and something that you are not? They deserve better for themselves and their lives. Even if they are in the dark about it, the truth of it insinuates itself into every crevice and facet of the relationship, eroding it, making it rotten and non-functional in most cases.

Some people will cheat to end a relationship. In my opinion, that is very different from being a habitual cheater while in a supposedly committed relationship.

No. I know several close people to me that were once cheaters, but not any more.

yes

No.

I have cheated, in all fairness this wasn't sexual cheating, but I did look for companionship outside of my marital relationship. Now I want my guy to be that companion, and would rather be single than with someone who can not be a companion.

The answer is unique depending on the individual... but my opinion is yes. If I ask a date, point-blank... "have you cheated?" and they say yes... Im outta there.

Like someone asked before - then, does this also mean once faithful, always faithful?

Circumstances change.

not always, people do change sometimes it may be a phase in the relationship that caused them to do it in the first place.

Past behavior is the best predictor of future behavior.

Anthropologically speaking, 80%-85% of all societies in history have not been monogamous.

What does that tell you about most males and many females ability to be monogamous?

I will disagree with you on that, because as we age a majority of people will grow and learn, and change in certain areas of their behavior. Such as maturity, etc. Some may not. What we did/do as youth we will learn from it and not do it again. I said a majority of us. How I was at 18 is not how I behave nowadays. Good day to you.

YOU GO GIRL!!!!!!!!!! GOOD GIRL!!!!!!

I would say no. People can change. If you do something once, you are not doomed to do it over and over again. You may choose to do it again or not. The harsher the consequences the less likely they are to repeat the mistake. The circumstances matter as well.
Were they drunk when they cheater or sober? That could make a big difference.

People need to realize the world is not black and white but also has a multitude of gray area.

Yes...the thrill is still there.

I disagree with the last statement because:
I believe that lack of moral standards is in place when it comes to cheating. One can not outgrow that because they were not instilled in one’s mind, and soul, to begin with; therefore, once a cheater, one might always be a cheater, and it will not stop, because there is not a learned behavior to do so; however, there is an existent and very real lack of morals and standards.

I have a confession. In my early 20's I was once labeled as a cheater. I am in my early 30's and I no longer cheat or have the desire to. People can change.

Well said.

So you are saying that it is impossible for a guy to cheat, then lose his wife and kids forever. That event then hurts him so bad that he swears of cheating forever because it is not worth happening again.

It truly depends on the person, the circumstances of why they cheated, and what they have to lose to where or not they will cheat again.