How do I get my boyfriend to stop flirting with girls and lying to me?

[Dexter]

Hi Amber,

Sadly guys don't change easily. If you're looking for way to make him changes, you might as well just leave him because he's not going to change. Unless he loves you so much that he'd do anything for you. Unfortunately, it doesn't seem like this is the case.

I don't understand why you love him, but this guy is a a big time flirt-er. And you know it. To me, I consider flirting is the same as cheating in relationship. And he's keeping secrets from you because he thinks you're a fool. But you're not. You knew he was lying and all.

I think there is nothing you could do to stop him from flirting with other girls. He likes to do that. And he's disrespecting you by doing that behind your back and even lying to you. And he will continue to do. And he might cheat on you one day with another girl. So think about this clearly and decide whether you should still be with him or not. You know what the answer is, but you just afraid to act on it. Well Amber, you're beautiful and I'm sure you're a wonder person. I think you deserve someone who's better than him. I don't think you guys would have a happy ending. So I think you should end it before things go too deep and you might get hurt even more. I wish you the best.