Thanks man! You're totally right and since my last post I made a lot of realisations I want to share, and I also still have an issue on which I'd like some advice from this forum.
So the same evening I posted this I read
this topic which also helped a lot for this problem. I realised that I just had to accept my feelings of criticism and frustration and also accept not just mine but everybody else's flaws and still love them for who they are.
I also realised during last weeks that being open and unreactive to my feelings wasn't enough but that I have to be open and unreactive to other people's feelings (as I said I am very empathic) as well. I do not have the powers to please everyone and I will dissapoint people by being me since I'm also a flawed human being.
Another thing I notice is that this 'wall' I'm putting up against other people happens when I'm tired and ran out of energy. Like the more tired I get, the more needy I become and the more I focus on the negative things instead of the positive (actually I think it's more like I lose my focus on the positive things rather then I start to focus on negative things. If I'm tired I really have trouble just making basic conversations because my lack of focus). So now I'm accepting the fact that I don't have unlimited energy and I need to rest to stay focused and therefore happy, and I'll try to not go across this border of tiredness.
All these things happened during the last two weeks, I had a project in which I met so many new people and had such a great time, especially the first week I was on top of my game, I had a huge status and I got so many IOI's from so many girls it was really incredible (like before this week I would have had trouble accepting this and I would just have put up a shield and be more introverted and less friendly but now I just accepted this and tried to stay myself, even if I realised girls were getting interested in me and who I'd possibly have to reject later). I also opened up more to people I felkt a good connection with and thus I think I made some réal friends as well, which makes me really happy. The second week tiredness started to kick in so that was a good exercise to rest and to find out how to keep myself on top of my game and not to get needy, so I had to keep myself more away from the crowd to think and try to get back some energy (is that what we call meditate?) and had less time for flirting.
Despite all this very positive things, I still have a long way to go to opening up and truly be myself and connect on a deeper level. There was one girl (out of many) I had a fun time with and flirted a lot with, like it was 'kiss a ginger day' and she was a ginger, so I told her that and said she might want to use it that night to get something from the boys. That night I didn't really see her again but the night after there was a party starting up but I was not getting into party mood. She however was and she pulled me over to start dancing and asked me about what I meant with this 'kiss a ginger day' and showing massive IOI's in such a greedy way I was really overwhelmed. Talking about this, dancing rzally close with her and the idea of kissing her ánd with all these friends watching was WAY beyond my comfort zone so I totally flinched and rejected her and got back to my friends (she tried another time like a few minutes later, the poor girl, and eventually she made out with another guy a few minutes later lol). And a little later I decided I was tired, not in party mode and needed to think and to sleep.
So I'm really happy with everything that happened because I think opening up to people and being so vulnerable just needs some time until I get comfortable with it so I shouldn't put too much pressure on myself, but I do want to get some intimate relations with girls and not flinch by the idea of a kiss lol. I think the fact that there were so many people watching didn't really help, maybe I had to find a subtle way to sneak us out without anybody noticing? But that would have been very hard anyway and I guess rumours would've spread anyway...