Antinatalism Arguments I think that people should have a liberal right to exit if they cannot find any alternative source of value.
I am truly saddened by the fact that you don't seem to find joy in life. Since I am not you and don't know your experiences, it would be presumptuous of me to suggest what and how you should think. From what I have observed and experienced, however, I think I can say that moulding our perspectives can play a big role in defining the good we see in our lives. Whenever I've met the financially less-fortunate people in my area, I've noticed that they are simply content with having a decent relationship and being able to sustain themselves. They learn whatever they can and say that they don't need to create some sort of ultimate purpose that transcends their "mundane" existence. Happiness is fundamentally subjective, so I believe that there is truth to the idea that we shouldn't have unrealistic expectations. And it's possible for us to have them subconsciously without even being aware of them. If someone had told me prior to my illnesses that reading my favourite novel would give me satisfaction that would outweigh the intense pain high fever brings, I would have likely dismissed them. However, lo and behold, this is precisely what happened. Sentient experience is quite diverse (and maybe that is what plays a major role in what makes life beautiful). I think that instead of absolute natalism or universal antinatalism, a nuanced approach is desirable.
You also raised a point that I see being mentioned frequently, viz., the fact that you wouldn't need happiness if you don't exist. Now, I actually believe this to be true (assuming physicalism is correct), but this is an incomplete conclusion. If we should not be afraid of/averse to non-existence because we cannot be deprived of something when we don't exist, we should also not chase/worship the void, since the absence of suffering has no value for an inexistent being. You're not going to be in some better/more satisfied state due to the lack of harms. In view of this, non-existence has no value/disvalue. What one does with their life, therefore, becomes a highly individualised affair that differs from person-to-person and what action/emotion brings them happiness when they exist. Lastly, I wouldn't say there's something "wrong" with you. I am not a fan of blind optimism. All I would say is that, considering that value only lies in existence, I think that it can be rational to try our best to discover a source of joy that can provide us happiness for as long as possible instead of seeking cessation which is necessarily limited in its capacity to provide fulfilment. Maybe some people are too uncomfortable thinking about non-existence so they quickly jump to therapy. After having discussed this issue with many individuals, I feel that I am not one of those aforementioned people. Nonetheless, I believe that therapy can definitely help. If there is an opportunity for gaining ineffable value that is more powerful than the temporary and slightly distorted satisfaction that the void might give, it may be the better option.
I hope that you have a wonderful day ahead!