Should I tell my boyfriend that I cheated?

Its totally up to you.. to know how he would react and if you really do love him i think being honest is the right way

Yes you should, because it will most likely always lie on your conscience. You don't want to end up going down the relationship longer with him without him knowing. If he ends up finding out later down the road he may feel betrayed and then those years neither of you can get back. Whether or not he stays with you or gives you another chance afterwards would be entirely up to him.

Being truthful and honest are both very important to maintain a relationship. Personally I do not approve of cheating and I would say yes, you should be honest as even if you lie to him now, you won't feel good and there are always consequences and ways of things going back to him. Allowing him to find out from other is more hurtful than learning the truth from you.

Honesty is the best policy. Keeping something like that from him is not smart. He needs to know, whether it will hurt him or not.

It would be wise to be as honest as you possibly can. If roles was reversed you must think if you would want him to be honest with you.

There are two approaches to this topic. Every person must decide for themselves what path they want to take. If you cheated on someone and you tell them, you are transferring your burden to the other person. But if you don't say it, you will have to live with the burden yourself. This is not the right approach though. This will lead in you feeling awful, every time you talk to the person you cheated on and if they eventually find out, it will a world of hurt, ten times as worse as if you would've told them sooner. If you really love them and they really love you, you will be able to talk about it and get to work through it. Ofcourse it will take time before everything will be back to normal, maybe it won't every go back to what it was, but that is what happens. Life will move on and you can get through this!

Have you ever heard of something called "the Golden Rule"? In a nutshell, if he had cheated on you, wouldn't you like to know about it yourself, too? Think about this.

What the worst case scenario here? And think about the best case scenario that can happen between you two

It is better to be honest in a relationship. You can expect him to be angry so be calm and ready to accept the consequences. If he still loves you, then you should commit that it won't happen again.

Yes, especially if you are sexually active. Everyone deserves to be fully informed of the activities of their partners. Your boyfriend needs to be able to make informed health decisions.