I think it should be better if you put it this way. "I feel less valued because my father doesn't seem to care about my safety."

I also felt less than valued, that my father didn’t seem concerned about my safety. If you force people to take a breath after valued (with a comma one small intake of breath) it makes more sense. The sentence has a punctuation problem, that is making it harder to follow. Some readers read punctuation as the writer wrote or wants it to be. Some readers ignore all punctuation. Other readers will put in their own punctuation where they think it should go. Double negatives can be used, but avoid the famous"we don't need no education" song lyrics.

It is correct but clumsy. Double negatives are valid, but.often hard to follow - I had to read your sentence twice before I understood it. Try rewording it without the double negative, it will be much better.

I also felt less than valued BECAUSE my father didn’t seem concerned about my safety. Because sounds better than that. You might also consider changing less than valued to "not cherished" or "unvalued".

Thank you Nanren888.