TBH never. I'm really not that interested in my inner world and don't have any questions about my purpose in life or who I am as a person - I think I look outwards all the time - life, people, relationships, etc are all far more interesting than whatever I might think about me and my mythical inner world. I definitely don't go in for any negative self talk - why do you think you are like this? What is it that you are worried about? You list:
unlikeable - is it that you think you don't have the close or meaningful friendships that you think other people have of that you would like? I enjoy conversations and time with other people but I'm very happy when I'm on my own - I definitely don't need other people - I don't depend on anyone for anything practical or emotional - I quite regularly go away for 5-7 days on my own (campervan) and I'm content if I don't see or speak to anyone although that rarely happens as I'm very happy to start up conversations with complete strangers. I suppose one of my fundamental ideas is that I'm more interested in adding to other peoples lives than subtracting - I'm not the sort that's inclined to dump any of my personal baggage on someone else's doorstep - I sort out my own problems in life.
less fun - than who? I have a couple of slightly zany, demonstrative, loud, confident friends who go round a room full of people like a honey bee pollinating flowers and... so what - we're all different. Do you mean less fun that the picture you have in your own mind about who you think you are or would like to be?
weird - well - tbh I tend to think the people I see using that word are teenagers - the over emotional, immature, rather self obsessed type - I find it a bit of a cliche. It's such an abstract term isn't it - it doesn't have a well defined meaning does it? Break it down into something more concrete - what do you actually mean?
annoying - give some examples. Maybe you are at times... but maybe you're not and it's all down to you thinking about yourself too much.
... I tell it to myself - this sounds like something to put your mind on - so why are you seemingly (imho) so self critical, self conscious and lacking in confidence?
I remember reading the first few pages of Charlotte Joko Becks - Everyday Zen - where she talks about her dog - who never worries about how he is perceived or whether he is achieving his full potential or making the most of life... or even if or when he will next get fed - he just enjoys life and play and people... she reflects that a lot of our problems - the human condition - are problems created in our own mind... and that - we could all learn a lot from how a dog experiences life.
I'd suggest you be open to talking things through with someone - and to think only in concrete terms - break down vague metaphors when you talk about things like being at the end of your tether, or in a dark place, or feeling depressed or anxious, or about bad mental health or whatever - break it down into what your real concerns are in simple, concrete, understandable terms - these might be the first steps to understanding and unlocking you from this (seemingly) negative self view imho.
I did 5 years of meditation classes and one of the things I got out of it was to realise that life is short - really, really short - (this was the so called "meditation on death") and that you can waste too much time thinking about yourself... I also remember some parable about a monk that was shot with an arrow - and they were asking "Who did this?" and "Why?" and the point (no pun intended) was that it was better to focus on getting the arrow out... and moving forward in life, not looking back or for explanations.