Personally I will be honest about this, it doesn't sound very healthy at all. Not to blame her or you, but both of you sound very emotionally and relationally immature. In your early lines you mentioned sexting iwth someone and wrote it off by pointing out that you were never "physically' with her. That means nothing, sexting is nearly just as intimately involved as being with the other person albeit without real physical touch. In every other way, it's just as sexually arousing, emotionally intense and is in and of itself cheating. She is no better by having had oral sex with another partner later on.

In a nutshell, I don't think either of you is entirely commited or ready for comitment of a full time relationship.

Counseling could help, but commitment is priority one, without that being there, no amount of counseling will fix your wandering ways.