Losing someone I truly care about is really an emotional situation, I would at times find myself not eating or having trouble sleeping, People reacted this way when there's the death of a loved one or a break up or a divorce, or a serious illness. It would stress me out so much especially I would even cry myself to sleep at nights. but I learned that this is what life is all about, something we all have to face when reality hits us. We have two choices either drown ourselves with our pains, shut yourself off with people we truly care about that are our friends, family, or we can let go and heal our heart and pains recognize what's underneath our pain, acknowledge it and maybe talk about it with someone you trust or your love ones like family or a close friend.
But, if something so small like if someone hurt my feelings etc. I would just blow the problem off, not gonna stress myself over it, because there's going to be difficult people out in the world no matter where you'll meet them at. 