I can relate to the sadness that you feel. I miss(ed) a lot of the family stuff too. My family is not very close and H's family consists of very few people. So, I just haven't trusted people and wanted to open up to them. Seems like I just get hurt. I feel like a sponge and absorb everyone else's negativity. You sound very sensitive. Which is good for some things, bad for some. It makes you very thoughtful and empathic for others, but it hurts your soul. Hmmm...is there a way to detach yet be close to others? There must be!
You sound like you are doing well with h. You grew up protecting your box so noone could hurt it. But not sharing your box hurts too. Perhaps little by little you can share it with h. The more he opens up to you, the more you'll open up to him and vice versa.
Things will only get better! And yeah, h does pick up on it. The best you can do is continue to work on it and fake it til ya' make it. He will see that you are becoming happier and more whole.