His behavior is different however only time will tell. His actions seem to indicate recovery but relapse is possible at any moment. this is early in the game. Change is hard... not only will he be changing but you will be (and have changed) as well. Personal experience... addiction is addiction it often manifests itself in a variety of ways. Healing only occurs when some of the "deeper"/root causes are addressed. Observe his actions on a wider scale.
Wether or not you decide to delay the proceedings with your husband is based on you, your son and your willingness/ability to tolerate/support him through his difficulties. You mention that gambling, inappropriate texting, chatting, phone calls with women and lack of financial support also cause strain on the relationship. Have/Can you forgive this? What reasons do you have to stay? How does continuing (or ending) in this relationship affect you? Is it healthy? You should determine what your boundaries are before you work toward reunification.
Good luck. Hang in there and take care.