It goes without saying, nearly, that the cheating was a culmination of a lot of long-standing issues. OP, ignore those who are only going to tear you down in this thread – I think many folks here have been there, have been tempted to get there, or have wondered what it would be like to have the same. Let’s face it – keeping a relationship going for the long haul is difficult work, and it’s not uncommon for one or both partners to start lacking, one partner to care less, etc. An affair can be enticing – it’s like being back in those dating days before you and your partner had to worry about paying joint bills or working or handling chores together. It’s all the fun without a lot of the problems you typically see in domestic life.
You’ve had to cajole your husband every step of the way. Even when you cheat, I find it suspicious that he reacted so calmly. Is he also feeling lukewarm – is he also possibly having an affair? Even if he says he’s forgiven you, give it time…this is something that can take a long, long while to get over. It’s a positive step that you’re moving toward therapy, but I do worry that now that you’ve had a taste of cheating, you’re going to choose this as your method of keeping him in line (“If you continue to slack, it could happen again”). That’s a dangerous ball game you’re playing, and it’s a game that’s not fair to you nor your husband.
Try to put off any contact with this guy for a few days. After that, stretch it out a little longer. Give therapy a shot.
It’s natural that you’re craving attention. Even with a guy who knows how to “work it,” so to speak, it can become bland, boring and routine after a while. A new partner can remind us that we’re attractive even to a wider audience outside of our marriage. You’ve been neglected for a long time, OP.
I can’t say if your marriage is worth saving or even if therapy will be successful – that’s something this professional can help you work out. In the meantime, try to take care of yourself, give your husband time to grieve if and when he needs to, and avoid any threats of, “I’m going to do it again!”
Your marriage may never again be the same, but if it continues, there is a possibility that it could be better.