-How long have you been married?
-Do you love your wife?
-Do you want to save your marriage?
Yes it may be time to seek counseling from a professional as a last resort before ending your marriage this way if you do decide to end it you both will know that you have tried everything you could to make it work and could possibly even end the marriage as friends and remain that way. It's obvious that you do have love for your wife or else you wouldn't be doing all that you can to make this decision easy for not only you but your wife also. You have to be commended for wanting to make things right and not wanting to hold your wife back but in all seriousness you have to be honest about your indiscretions if you do decide to go to counseling. It's important to be truthful and fore coming about what you were doing during the marriage. Ending with a clean slate is much better than living with a lie that will eat you up. I would give the counseling some time before making your final decision and give it your all this will make things better and possibly could mean saving your marriage, you may find that with the counseling and time talking things through that a divorce is not what you want after all so if you go into to it go in with an open mind and consider all of your options at this point.
Only tell her if you plan on staying in the marriage, I say that because if you decide to stay and this lingers over your heads it will eat at you and no matter how many you have told it does not change what happened and you really haven't told the person that really deserves to know. If you are planning on leaving the marriage and divorcing then I see no point in telling her, the marriage is over and that would add insult to injury so to speak but if you decide to do counseling and she asks if there were others you need to come clean you will be surprised the burden that may be lifted off of your shoulders.It seems like you may have had or still have a sexual addiction also which goes hand and in hand with other addictions so it's good that you are in a recovery group that can really help with that. The finally decision is yours to make but I would seriously consider marriage counseling also.