Was it a sex starved marriage because you turned to porn instead of your wife? Or did you turn to porn because she wasn't interested in sex?
Were her threats of divorce over all these years about the porn, or were there other reasons she was unhappy? Or is this part of an unhealthy pattern she has?
Do you have other addictions besides porn?
Some thoughts: First of all, own your part in this. Validate that the porn was inappropriate.
Second - about GAL. Tread carefully here. In your situation ( a little different from most) you DONT want to give her the impression you might be out meeting other women. So engage in healthy activities with male friends, or if you have kids, focus on spending more quality time with them.
Third - why are you so financially strapped? Is this another issue in your marriage that needs to be addressed?