Completely your decision if you want to remain together, build your strength up and confidence, you have been hit with a steam roller.
Nobody makes great decisions whilst they are dealing with trauma.
Forget the decisions for now.
It will take you years to heal from this betrayal and the journey is one that you should steer. He needs to step up and be very kind to you, if not he's better off away from you.
Part of me thinks sleep with someone else, befriend another man, allow that to happen but that normally doesn't happen because the betrayed are usually so broken they believe no one would want them.
Anyway, like a pp said this will take at least 2 - 5 years to even start loosening the pain from your thoughts, it's horrendous, whether you are together or not, it's a long journey.
It's the feeling safe part that is hard to get back, the women who overcome betrayal and remain together are usually the ones who have worked on becoming self suffiecent in the marriage and not leaving themselves 'open' as it were.
You can still have a marriage but one that is not fully open and surrendering, you will always have your guard up for protection, it's innevitable.
Part of the magic has gone and that is very sad, the saddness can be overwhelming, some cope better than others. The strength you need is collosal, are you strong enough, do you want to be strong enough, does he deserve you being strong enough.
6 months in and you are at the beggining of questioning everything, there are no shortcuts.
There really are no quick fixes, but really do not put pressure on yourself to become happy again within a time frame, allow yourself the freedom to change choices whenever you want.
Think of yourself, your needs, your wants, your health and do not let anyone pressure you either to go or stay.
Build yourself up so you are the one making all the decisions, it is your life and someone has hurt you, you don't have to forgive or even be able to.
You are not yet in a position to know whether you are able to yet.
I admire you giving it a go though, as I admire any woman who has been through betrayal, staying or going it doesn't matter both are unbelievably fucking hard.