I'm new to this forum, but not new to the subject.

I need to know your opinion on this, so my story, short:

I am what you call an Alpha guy, I'm the kind of person who usually is the center of attention at parties, or in other groups, I am an extrovert and usually I have a natural way to be liked by girls (many times I don't know what is exactly that I am doing) and respected by many people. However, my problem is that I have a girlfriend ([b]this is not about her, but it is relevant, so don't erase my post[/b]) for a very long time, and not only this but she was the first and only girl with witch I had sex. Now for some time we can't live together (she is from another country) so this means I should take advantage of this chance. Now, I don't know why, but I have, or should I say had, a very powerful sense of duty and loyalty, I was loyal to her not especially because I care about her, witch I really do, but because I wanted to be "a man of principle" and this kind of thinking let many of my friends think I'm weak or stupid, and most interestingly, many girls like me because of this (witch of course made my GF many times jealous... hehe). I never really cared about these things.

So this is my problem:

Now I decided to do something, because it is a very important experience witch I almost completely lack, but I discovered that I have one big problem witch occurs most of the time. Although it's fairly easy for me to generate a lot of attraction and I have no problem with the physical contact, when I have to pass on to the next "level" like more intimate kino or going for the kiss, I simply stuck and don't know what to do. It's not like I'm afraid, it's more like I simply don't know what should I do next... it's like until that moment I don't need to think about anything, everything comes so natural to me... but at one specific moment I "wake up" from that state and start to think and begin to behave very awkward like suddenly being silent, hesitating and so on... from here everything begins crashing down. I am sick and tired of this, it's getting so frustrating, I finally decided to write about this after another crash yesterday with a girl who seemed very into me, but after I managed again to ruin the mood by starting to behave very strange, she almost LJBF-ed me.

I need any kind of advice about how to control this part, how to keep that "don't give a damn about it, just play" attitude more and be comfortable with the "phase change.