Porn is passive, you're watching something that was already recorded and you can't interact with the actors/actresses. That's what makes it impersonal, and something I do not consider to be cheating. However on omegle you actually interact with other people, you can chat with them or even talk with them over mic, which I think breaks that passive "porn video barrier". The only difference here is that there's a computer standing between you and whoever decides to help you get off. Whereas the difference with a porn video is that yes, there's a computer standing between you and the porn stars, but there's also actually no way for you to interact with them and it isn't (most likely) live either.
Next time ask yourself, is this something your girlfriend could also do? Would you be ok with her going on omegle to interact with other guys, and to masturbate with them? Or would you be ok with whatever other things you're thinking of doing behind her back? Also ask yourself, is this something you could actually tell her? Or is it something you would do your best to hide from her and/or lie about?
So,
- if she can't do it/you wouldn't be ok with her doing it
- if you have to lie about it or hide it
then it's cheating. Very simple.
Ask yourself how you might feel if your girlfriend did something like this, and how you would see it? If you don't think you would like it, sure enough your girlfriend won't like you doing it either. Porn is not interactive - no girl in porn will know your name and not even know you exist, but Omegle is when you do talk with them and it becomes personal even if you don't exchange contact information.
What you're doing on Omegle is to my knowledge, video and chatting and getting sexual with people you don't know. In a way, it's very much like FaceTime sex with your girlfriend. So if what you're doing is the same thing with one chick on Omegle, but you reserve that for your girlfriend otherwise, then it's not okay.
Again, just think of how you'd feel if your girlfriend used this logic that she couldn't FaceTime with you so went off to use Omegle to get her needs met. If neither of you mind, then fine. If you both mind, then it's not okay.
Why won't you just do that with your girlfriend when you can and when you can't do it, use self-control
It seems you've learned your lesson, but I'm gonna explain why I think it's wrong. While porn is impersonal and just pictures/videos Omegal is an actual person you are actually reacting with. If it were porn it'd be different because it's like a masterbation aid (like a dildo or fleshlight) and you aren't actually interacting with the person to get off. On Omegal you are having virtual sex with a person who you are interacting with.
While this isn't exactly on the level of having sex with another person it is still cheating and it is still wrong if you. Talk to her about a way you can be sexually satisfied without having to go to other people because going to others is wrong!
If you are having any type of sexual activity whit the person you shouldn't , It's cheating.
Scroll Down to Read Other Opinions
What's Your Opinion? Sign Up Now!It's cheating. I don't tolerate it.
That's definitely cheating.
Anything you don't want you're partner to find out about is considered cheating.
Let me guess: you met your girlfriend on Omegle?
Yeah that's cheating
Sexual Relationships 
Sexual Health 
Most Helpful Girls