That seems to come with the territory. My body reacts really badly these days to anyone not ultimately good for me, no matter how likable they may be, etc. Manic people are the worst; the energy overrides my own and stays with me for days. Can't bear the dragging leg pains I get around certain illnesses, also.
Not quite 38... You are young! Don't panic and hand over your best years to some crazy man who lovebombs you on a first date and will burn you out in a short time. (I've picked the crazy/nasty ones, unfortunately, so look back sadly at that aspect of my life, but boy do I know a whole manual of red flags now!)
Sorry your date was a fizzer. It's not you. It's the condition - we are magnets for all sorts of trouble, and troubled souls. Some empaths seem to thrive on it and feel it is our noble duty, but it tires me right out these days.
Also: I am not big on the Law of Attraction. Don't think you need to 'improve yourself' and certainly don't think you should blame yourself for these peeps being attracted to you - but you do need to learn your own boundary, and what is good for you, and maybe slowly make some decisions around all of this. Once I got firmer, and clearer, I felt less of a terrible person for assessing that yet another sick person was not a good idea for me as a new best friend, etc. Long hard work to draw those lines and lose the guilt, though.