Telling him I need space without rejecting him

My 3.75 year old is driving me batty. He constantly needs to be on me, touching me, telling me he loves me. He is so needy of me. If he's happily sitting with DH or DS1 or DD, and I sit down with them, but not next to him, he will get up and come and sit on me. If I sit to watch TV, he will come and sit on me. When he comes to our bed through the night, he sleeps on top of me, if not literally on top of me, then he's on my pillow nose to nose arms and legs draped over me. He squeezes my fat rolls and arms and boobs for comfort, despite me telling him I don't want him to do it, that I don't like it.
He goes to day care twice a week, and is happy enough to be away from me. It's just when he's near me, he has to be with me, on me, touching me.
He was a fully demand fed breast fed baby, until he was 2 years old. He fed very frequently and fully co slept with me from birth. I weaned him almost 2 years ago now, and he's had his own bed since just before he turned two (although he comes to our bed almost every night). I have been trying to gently tell him I don't want him on me all of the time, that I need personal space, that I don't like him touching me like he does.
It's his comfort, and I can understand that, but how do I gently get him to understand he needs to stop, or at least not do it so often. I could cope with once or twice a day, but I am starting to get really frustrated with his need to touch me, to be on me, and at me all day. I don't want him to feel rejected by me at all, but I am starting to get anxious or kind of phobic of him touching me. I will move away from him, put physical barriers between us, just to keep him off me. I don't mind him sitting on my lap, but he has to have his hand in my top, or squeezing/pawing at me.
Please help me!!!

I had this with DS at that age. Still do and he's coming up for 8.

I just tell him that I don't want to be touched. He can sit next to me, but not touch me. I still love him and I'll let him know when it's time for cuddles. But I do tell him and not just make a barrier, as that would confuse my DS (however, may be the better option for yours, as I don't know him). I have told him that I don't like to be touched in certain ways and if he does that, we don't touch at all. DH backs it up a little too far, but once he's old enough to realise you are your own person and have your own body and likes/dislikes then he's old enough not to squeeze you because it hurts you. (Even if it doesn't, it is easy to understand at that age and trying to explain the emotional pain from a physical touch isn't easy, even when they're older.)

Because we respect his personal space boundaries, he is able to respect ours (with reminders - he still loves playing with my hair to the point I want it all shaved off). HTH and good luck with getting your body back.

My son has sensory issues so he used to paw away at me and drive me mental. I tried to replace the need for touch with something else. Perhaps you can work with him to find a squeezy toy he likes that he can fiddle with while he sits with you?

That was/is my youngest son. He always wants to touch me.

What I did was say I needed my bubble time, which meant no-one came into my personal space (i.e. my bubble) for x minutes. This includes everyone, even my husband. I would tell my son he could have a big hug first and then no touching until the time ended. I used an egg timer and just gradually increased the time.

I am not a touchy feely sort of person and being touched all the time was very difficult for me. We are now up to 30 minutes on his really touchy days but we can go some days with only about 10 hugs.

I did have issues with my youngest transferring his 'touchiness' to my eldest which caused some issues as my eldest son is like me. So now when I am in my bubble, so is my eldest son.

Thanks everyone. I have been telling him I need space, and that sometimes I don't want hugs or kisses or touches, like when I'm washing dishes, or vacuuming.
He's slowly getting better at listening to me. I think the worst part is that when I tell him to stop he will for a second, then comes back. He doesn't understand I mean stop, for longer than a minute!
I am his comfort. Over the years, I have tried giving him a blankie, a satin pillow case, a teddy. He took up the teddy, but only at bed time. And if he wakes at night, he comes to me for snuggles.
We are just reiterating that I need space sometimes, he is ok if he doesn't cuddle me every 2 seconds, I know he loves me lots, and don't forget in 2 seconds after he's told me 10 times and that daddy is here for cuddles and loving too.