Is it only me or others also feel the same about their relationship?

It isn't considered the earmark of a good relationship if one partner steps out on the other and the other isn't allowed to do the same, or doesn't agree to those terms. It's selfish and self-serving of the one who looks for multiple partners but expects their main partner to stay monogamous.

If it is not what you want, if it is not how you define love, then perhaps in the long run, this relationship is going to cost you a lot of emotional pain. Only you can decide whether or not it is worth staying.

I’m living one myself. I love him, yet he won’t even make it exclusive, therefore the best way not to get hurt is to deny the relationship bit. If he’s not mine only, then there’s no relationship.

That's why they make Sharpie markers.

So you can write your name all over their junk.

not for me. I know of ppl who claim that they like that life, but ... no.

Obviously not, you know this.

Definitely not a good place to be.

Monogamy is the way to go.