how do you be around your boyfriend (or gf) when you feel numb?

I have days where I just go numb. I have an extremely difficult homelife, and its taken a tole on my emotions over the year. I've recently gotten into my first relationship in four years, and I'm still getting used to all this. On days like today, when things get rough, I go completely numb. I lose all emotion and I basically become emotionally cluless and awkward. How do I deal with days like this when I'm spending time with him? I dont have the want talk let alone kiss him or joke around like I usually do. Its no ones fault but mine, and I just dont know how to fake it at that point. What would you recommend?