In order to even begin fixing this I think you need to work on your feelings of inadequacy. It resonates in all your posts. IMO, this is something that you really need to work on in IC. You can't love someone else well if you don't love yourself.
Also, please don't minimize! "Only Oral" is cheating. If you believe it's not 'as bad as' intercourse, you're not owning your shit.
Owning your shit is key to recovery from infidelity.