Hi,
I think that it may be true particularly when it happens in childhood, for example in cases of direct abuse or vicarious learning ( a child having seen his mom being abused). I know this is a theory ( I mean learned helplessness) and as such it has being reformed and also criticized. To me, attributions theories are better. I identify myself with learning from my mom to be helpless ( not that my mom was abused as far as I know, but that she was always hoping for the worst and verbalized it all the time due to high anxiety and other traits she had).
In adults, I think it is different, as an adult basic learnings are already done. Normally people have the tools to face a series of negative events, unless these are extraordinary ( such as in situation of torture, war, etc) or that the adult person is suffering from a mental disability now (for example being under depression). The one million question is: is the person feeling helpless because of depression or it is helplessness as a stable inner perception causing depression long term?
Another thing that comes to my mind is that human learning is not equal to animal learning. In my country we are more focused on Non American psychology but I believe that many American theorists recognize the difference between the two.
The last thing you may want to consider is resilience as a complement to learned helplessness theories.
Personally, I think you have had enough negative events to feel helplessness right now but that does not mean your ability to be more hopeful is permanently impaired.
A hug