There are some guys who stay loyal to a relationship and then there are the “playboys”. You are with a playboy and the chances are pretty slim that he is going to become a “one girl” man in a short time.
Frankly, the line about “I left them all for you”, is quite a common one that most playboys use to get their hooks on a girl. Like a zebra never chances his stripes, a playboy can never control his urge to get into new girls. It’s his addiction.
So what do you do? If you are in the relationship for fun, go on with it. But if you are in this relationship for “commitment” then forget it. That’s not going to happen with this guy. He will never stay committed, no matter how much you love or care for him. Being a playboy is his “character” and that’s not going to change.
It’s a waste of energy on your part to try to change him. You will feel let down and cheated if you harbor the expectation of getting to be committed to you. There are some girls who are okay with the “playboy” attitude of their boyfriend, or even their husband, but frankly, it’s not a very healthy relationship to be in. Such girls usually have a low self-esteem and are “needy” by nature, so they cling on to the guy even he treats them like a “nobody”.
It’s your call. Just don’t bother changing him, because it won’t help anything. You need to take a decision on what you want. Are you okay to be in a relationship with a guy who is a playboy? You might good reasons to stay put, but fidelity should not be one of them.
Remember that there are lot of guys out there who are “one” woman men. So it’s your choice in the end, what is it that you want from a relationship.
If you feel used and exploited, then there is no reason to stay on. You will have to share him with his girlfriends if you want to be in the relationship. There are some girls who are quite okay with such a situation. Are you willing to be one of them? Your decision will be your responsibility; don’t blame the guy because ultimately you have the choice to “stay” or “leave”.