I found a counselor very helpful to objectively and at times obsessively review my relationship. I too recommend Codependent No More.
The best thing I found was turning the energy of what ifs towards self reflection and self change. There is wisdom to working only on what you can change ~ you.
I really found several of these articles very helpful in understanding and letting go on all the addict’s lies and deceptions. In the end, I was most angry with myself for accepting a relationship for so long where the booze was a mistress.
Take the time for you. You deserve it.
Addiction, Lies and Relationships