How do you feel about relationships today compared to years ago?

I am not sure how people did things many years ago(maybe like 20 or more years) but it seems like in today’s society(at least my experience) people tend to think that multiple sex partners or dating more then one person is acceptable and should not bother the other person. I can understand this if you just met the person for a week or two but once you continue to see someone or things begin to get more serious I personally think your focus should shift to just them. Myself personally tend to focus on one person as soon as I have interest. I feel that’s only a fair amount of respect to give to someone that you are interested in. My question is, what is your take on this, were things like this in the past or do you think today’s society is losing it’s value on relationships? Do you personally think (or act) that when you meet someone it is okay to continue with multiple sex partners/dating more then one person or are you exclusive when you begin to see someone.

Also just to clarify, when I say date or see I do not mean that you have promised to be exclusive to one another. I think that goes without saying that if you promise that, that is what you should be doing.