Hi! I believe I can be of help with this issue.
First, let me say I can imagine how confusing and distressing this situation must be for you. You want to be funny and lighthearted. It's what you perceive as being the desirable "you". But you've already identified who and what your are inside: serious.
Now, let's be as open and honest as we can here, okay? A person does not create a separate outside and inside casually. And when a person does split himself like that, after a while, sometimes short while, sometimes longer, he loses it. He can't keep trying to maintain both selves.
There are many reasons why someone might want a separate outside, why the inside isn't comfortable and doesn't feel natural. I'm working in therapy with one person now where there was an alcoholic mother and a father who was emotionally not there and meek and just put up with the raging and alcohol. The man when he was growing up learned how to hide his "self" from view because it wasn't safe. It was easier to retreat and just put up an exterior self. This is not the only scenario. But the point: there are important psychodynamic reasons, reasons in one's childhood and youth that drive a person to have an outer self and an inner self. One man I worked with was bullied throughout junior and high school, for example.
Keeping one's inner self "safe" is the number one reason for creating the inner/outer divide. And this is the problem: now that you are an adult, relationships require emotional intimacy. Not just sex, but emotional intimacy. And that means opening up one's boundaries and revealing and sharing one's inner self. And having friends means emotional openness. Not just creating a funny self, but opening up what's inside, the funniness inside, feeling open enough to let the funniness inside come out.
The first problem, then, is that this is not safe for those who have the inner/outer divide. The second problem is that after a number of years and decades, they themselves no longer are so sure of who that inner self is sometimes. It becomes a shadowy figure, someone who makes them do things but they are themselves not safe with. This is often what I need to work with in therapy with people: who is he inside is not so accessible to him! And this is often what a person means when he says that inside he's "serious".
So, we are at a bit of a quandary. You are hoping for tips that I could give you. And I've described the situation as being something so intrinsic to who you are as a person that it is a very deep issue. It's not a matter of applying some surface tips like taking Vitamin D and increasing your exercise time. It's a challenge that you have to be wiling to take one: the accessing of who you really are inside and the courage and motivation to share it with others. Because if you really are serious inside, then sharing your seriousness will be accepted with approval and happiness by people when it's really who you naturally are. And if you're funny inside, then that natural funniness is what's called for. The key? It's the naturalness that people respond to, not whether you're funny or serious.
That is not to say that there is nothing you can do on your own. I mentioned motivation specifically. Because it is an area of self help that there are excellent resources for working on bringing out who we are inside. But I also recommend that you consider working in psychodynamic therapy on the inner/outer divide as well.
Motivation: I recommend you apply the principles in the following videos and books. So that you can be yourself with more confidence and share it with others. Coach yourself. Be your own life coach! I want you to get really into motivational videos and books. In other words, accept your past fears, accept your past worries and hurts and traumas. Accept them and focus on becoming who you WANT to be now. Here's a simple YouTube search I put together on "motivational speakers":
http://www.youtube.com/results?search_query=motivational+speakers&aq=f Some like Tony Robbins are the classic big guys. Some are newer. There are now wonderful women speakers as well. There are now great women speakers as well. Watch them all. Get inspired. Buy a book or two. Here are some possibilities, but they are only suggestions as there are so many good ones.
The first book is the father of all these type of books. How to Win Friends and Influence People by Dale Carnegie. There are classes in these books now! It was written in the 1930s and still has something to say to us today that is very worthwhile.
I think very highly of the second book on my list, which is a real classic: The Seven Habits of Highly Effective People by Stephen Covey. It is the book that has helped more people than probably any other. The third book is by Anthony Robbins. He's one of those speakers who fills up huge auditoriums. For a reason. He's a terrific speaker and writer. The particular book (if you like it, try his others): Awaken the Giant Within.
I recommend you also get to a meeting of Toastmasters and become familiar with that organization and their training opportunities in public speaking. It will REALLY help you to learn to be natural with people to learn public speaking. It's been around for decades and in my opinion is still the most trustworthy organization in this area. Here's their meeting finder but browse their website as well:
Psychotherapy: the opportunity here is to gain a greater insight yourself toward yourself, who you are inside, and how you might want to project it toward others. Let me give you two directories to look at that are good. You should focus on finding a psychologist or psychotherapist in your area who practices in a psychodynamic orientation.
Here is the web address for Psychology Today's therapist directory. You can sort by zip codes and when you see someone who seems like they might be helpful (because they seem smart and not so easily manipulatable!) look at the listing and see if they list psychodynamic therapy in their orientations. http://therapists.psychologytoday.com/rms/
Good Therapy is a non profit directory. Same idea as the one above:
I wish you the very best!
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