Fibromyalgia Support Group
You're not alone in your pain. Fibromyalgia is a condition that can be difficult to diagnose and manage. If you're trying to cope with pain throughout your body, sleep problems, general fatigue, or other common fibromyalgia symptoms, you're in the right place. The community is here for you to talk about therapies and share your challenges.

I assume your family knows about your diagnosis? Since only you know what does and doesn't hurt, I think you'll have to explain it quite directly. Maybe explain that generalised muscle and skin soreness is very common in fibro, and that even loving things like a hug or a squeeze of the shoulder can hurt. If hugging is important, maybe suggest that rather than pulling you into an embrace, maybe they can open their arms so you can initiate the hug, and then they hug you back as strongly or as gently as you hug them?
I'm an extremely non-touchy-feely person even without fibro, so I'm one to thrust out a hand so I can shake hands with people when I can get away with it. And I live in a culture where the typical greeting among close friends and family is giving three "kisses" (touching alternating cheeks together while making a kissing sound in the air), so I don't have to worry about a lot of physical contact, luckily.
With my partner I did just have to explain what is and isn't possible. I still have to remind her to be more gentle at times, but fibro also has better and worse days. It's not like she know inherently when I'm extra sore, and she always clearly feels guilty when I indicate a loving squeeze was a bit too much, so I'm never upset with her about it. It has to be an ongoing dialogue in our relationship.
Hope you'll find a way to talk to them so you can be comfortable. And welcome again.
You can also do the "shoulder touch" hug, which my hubby has perfected. It's like the classic "man hug" in one sense. You angle and aim so that all you touch are maybe, briefly, your shoulders for a second. I'm a big hugger, but ow ow ow sometimes anyway.
Try describing it as the worse case of flu that they have ever experienced that continues 24/7. Or, how badly a person feels after an intense workout at the gym the next day. If nothing else, just make it a habit to say something before you are touched. Take care.
I have a really hard time with my kids on my bad days bc they want to run up and hug me or play with me and i just can't. :( a couple of weeks ago i was sitting on the couch and my almost 3 year old pushed down on the top of my leg to get up there with me and i started bawling bc it hurt so bad. Then she started crying bc she had hurt me... lol
When I was hanging out with my aunt recently, she ended up spraining her ankle while trying to take a photo and stepped backwards into a ditch. When her ankle was swollen, stiff, and painful to the touch, while changing the wrapping she happen to ask what fibro is like... I told her to imagine that sprain all over her body. She responded with big eyes: "OUCH!" Suddenly she was the nicest person after that and told me she admired me for always finding a way to smile during the day despite feeling so crummy and doesn't know how I do it. :).
As far as my family goes, they wait for me to initiate the hugs. My husband had to retrain himself because he used to like to tap me playfully on the butt. Now he walks up to me and rubs me on the head instead. lol
Great article about the different types of fibromyalgia.