It sounds like you have been taking things slow which is great, when you have children the last thing you want is to jump into anything that may hurt you or them. As for being a rebound, I do not suspect that this is the case. A rebound typically is when someone jumps into a relationship head first and gets caught up quickly. In your case you have handled this well.........getting to know each other and just communicating.
I think continuing with this may be a good thing for you and your children. Just because your marriage did not work does not mean you should give up completely. It just means that you are a little more experienced and need to take it slow.
I would suggest continuing what you are doing now and maybe setting up a date and go from there. Take it slow and get to know each other and at your own pace. Of course you already know not to jump to fast. The key is to look at this and not the past, of course you are going to be weary after what you experienced before but the fact remains that not all relationships end in such a way and not everyman is going to be like your ex. Give your new friend a chance to show you who he is by taking it slow and enjoying each other.
I know it is hard jumping back into that pond, but as long as you are keeping your eyes open and giving him a chance to show you who he is then you are unlikely to make the mistakes you are afraid of.
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