I don’t think you should give him the silent treatment. Since you guys have already kind of had this conversation once, he needs to hear from you what you are feeling and what you plan to do. The silent treatment is really awful for people who really care about you. And it also leads to more mis-understanding. Unless you tell him why you need to distance yourself from him, he may grow to resent you, or he might think that he did something horrific to you and he won’t know what it is.
You need to talk to him very sweetly and explain that you have very strong feelings for him (or even love him, if that is the case). But tell him in no uncertain terms that you need more in your life than just a “friends with benefits” kind of situation, which is pretty much the definition of what you have. Also, you can tell him that you often feel confused because he has told you that he doesn’t want a “relationship” but that is kind of what you guys have (in the most basic sense of a relationship).
It’s a real relationship, but it isn’t a particularly good one, at least from your side. Let him know gently, that you understand that he isn’t at a point in his life of being able to be exclusive with you or anyone else, but then tell him that you simply can’t continue dating and having sex with someone who can’t give you that exclusivity. Exclusivity may not be important to everyone, but it is extremely important to you. Let him know, gently, that you guys just don’t have the same life goals or values and there’s nothing wrong with that. You just need to be with someone who more closely parallels your ideals.
And you can gently point out to him that you are not asking him to marry you and you are not giving him an ultimatum, you are simply letting him know that you can’t remain in a situation that feels like limbo to you. And because you are 32, if you actually do want to get married and have children, you need to be preparing to do this right now (I don’t mean hunting down a husband, I mean simply moving forward into a better situation that is likely to lead to marriage and children). Sure there are lots of fertility treatments for older women, but your odds of getting pregnant diminish greatly after age 35, even though there is plenty of anecdotal evidence to point out that women do have kids well into their 40’s.
You can just tell him that you realize that you are both in very different places in your lives, in part due to the age difference. That is not an insult to either one of you, it’s just the reality of your lives. Most guys in their 20’s are not looking for a commitment. Most women in their 30’s are looking to build a committed life with a mate and start a family.
All of this conversation is not meant to punish him, or for you to have some sort of dramatic exit. It’s only to let him know what you want and need and how you plan to go about living the life that you need. That may be by walking away from him, and maybe the two of you deciding to talk in 6 months to see if anything has changed (for either one of you). But let him know that the reason you might want a no-contact rule is simply because it is too painful for you to be “just friends” and you refuse to continue being “friends with benefits.” None of this conversation has to be yelled and you don’t have to cry and no one has to be the bad guy. It’s just two people talking about what they need and how they are going to go about getting what they need.
If you don’t think you can have that particular conversation immediately, then just tell him that you need some time alone to think things over and then plan to get together on a certain date or in a certain number of days (like a week) but please don’t give into the temptation to give him the silent treatment. I think you would ultimately regret it.
Good luck to you my dear : )