Is mistrust in a relationship immaturity?

It seems to be common couple behaviour to see red when one of them hits the town with their friends. More so if they don’t call by the end of the night. Checking each other’s phone for messages from the opposite sex is the norm too.
Surely if a relationship has got to that point it’s time to get out? It’s not always the jealous person’s fault either. Sometimes they’re not given the security they need. I wonder if some enjoy making their partner the green eyed monster, playing mind games because it makes things interesting, gives them control, and means the other person cares. There’s always fuel added to the fire. Why not just be respectful to drop a text through the night to see how they’re doing instead? Otherwise, you should question whether it’s fair to even start a relationship. Just be single and free to date like-minded people.

I’ve found, in my thirties I can’t be bothered with games. I walk away as soon as there’s signs of this immaturity. I have too much self-respect to allow myself to be treated so even if I did love him. My mindset is, if a guy tries to fuck me over, then his loss. It’s not the sort of person I’d want in my life anyway. I’m comfortable within myself and wise enough to realise he just wasn’t the one, didn’t deserve me and there’s plenty more fish in the sea. I certainly wouldn’t lose sleep over it.