Suga... you mention giving too much... you shouldn't. You need to consider yourself first.

And I don't know how far you are into the spiritual/alternative approach... but for me when being around people, it greatly helps to create an energetic shield (it can be expandable/flexible aura, an "egg"...). Oversensitive people tend to pick up on the negative vibes... and there are people who feed of others. I don't want to go into this further, in case it might be triggering for you... but it might protect against some of the feeling of vulnerability.