I think what you need is a little bit of patience you have only been dating 4 months and after what his wife put him through he is probably still healing from that and you have to give it to him he is being completely honest with you. Just because he said he isn't in love with you doesn't mean in time he can start to have love for you. He may be scared but I don't think it will last forever like you said he is good for you and doesn't lie that is very hard to find. Maybe think about going with the flow for now and see what happens later on down the road. Enjoy what you have with him now and if you feel uncomfortable about him dating others mention it to him but that may not change the way he feels and he did say that he would only be intimate with you, he may just want to weigh his option and not move too fast. If the divorce was recent then he probably still has open wounds from the way the wife treated him during the marriage that is a hard thing to get over especially when was married for 20 years.
Give it some time and if you are still not satisfied after a few more months maybe you should sit down and talk to him about your concerns or sit down by yourself and decide if this man is the right man for you and if you want to live you life in this manner or wait for him. Just give him credit for being honest with you and not seeing other women behind your back but if it bothers you don't settle just to make him happy let him know how you truly feel about him and the situation this way both of your feelings are out in the open.
You're welcome and if you ever need help in the future please don't hesitate to come back to Just Answer.