Am I just really old fashioned to think that love doesn't involve cheating the first time there is an issue in the relationship, shouldn't be easy and generally should be a secure "bond" between two people and that intimacy (to a degree) should not be tossed around like a meaningless word

I don't think anyone feels this way even though it might seem like it. The thing is, we live in a day and age of instant gratification which social media has largely added to this problem. A new relationship is a swipe away and people are easily replaced. Why bother putting in effort to solve hard problems when you can just roll the dice again?

Nothing of what you've said is what I would consider old fashioned. Usually people wise up to the view you have on things as they get older but personally I'm less forgiving in this regard. I think it's pretty much a joke that a large amount of people, especially on Reddit have this view of "what's in the past is in the past" but it is what it is.