Keep in mind that most of what you're experiencing is common to a lot of other people. You're not at all alone. You're not in a situation where everyone else is succeeding and you're the only one that's struggling.
HN (and similar sites) primarily focus on the success stories, and it is very easy to let that warp your perception of your efforts, your abilities, your projects, yourself.
You may not have what it takes to launch or run a startup. Nothing wrong with that. You'll be in great company. If the stress of trying over and over again is getting to you, if you're feeling defeated, then stop. Step back, regroup. Think about what it is that you really want: do you want to be wealthy? There are other ways to do that. Do you want to make a difference? There are many ways to do that. Do you want to build cool stuff? Inspire others? Live a comfortable life with a family? Those are all OK, focus on them.
What you describe in your last lines sounds like depression to me, and it's a common problem too.
Point-by-point:
> I tried during 5 years to create a "startup".
Why? What was your motivation here?
> I still have a half time job that pay the bill and give me enough time to create something.
So, you're not yet fully committed to living or dying by your work. That's not necessarily bad, but realize this, because it's important: the less fully committed you are to your projects, the less likely they are to be successful.
> During these 5 years I created a game, a tool for geeks, a B2B project and lot of more things.
This sounds unfocused to me. If we step outside of the startup drum circle for a moment, you'll find that a lot of businesses will spend around 5 years just trying to develop, market, and popularize a single project. The startup iteration cycle produces really amazing results when it works, but it also produces a lot of failures. If you've got the sort of personality that is discouraged by too many failures -- and again, you're not alone in that -- then maybe you should look at some of the more traditional business models. There are some very successful, under-appreciated people in our industry who have done just this.
> Each time, I have no traction, negative feedback, I demotivating and then I stop the project.
A successful project is one that you do not give up on.
> Each partners I meet seems too newbie to work with.
Is it possible that you're holding them to the wrong standards -- i.e., they're not "YC material" -- or that they've giving you good advice and you're not following it because it doesn't fit in with your expectations?
I don't know you well enough to give you more specific advice. (Nobody here does.) I deal with some of the same issues. Here's what I do to work around them:
- Change my mindset. I often remind myself that although things are not where I want them to be, they are still better every year. And, although I'm not running a multi-million-dollar-per-year business, I've still managed to make a real difference in the lives of other people.
- Make sure finances are comfortable and stay that way. I'm not rich, but I try to keep a little bit of slush in the bank, it keeps me from stressing too much about other stuff.
- Keep an active side project, something that I enjoy working on, that has no deadlines or associated stress.
- Take time to decompress, spend some time alone, recharge, whatever -- but find the desire again to keep chipping away.
- Realize that, even at 35, I'm still fairly young and the game's far from over.
- Just keep building. Even if it's just 5 lines of code on a day where I really don't want to do it, it's still progress. Everything I do leads in to the next project, the next step towards my goals. I build momentum this way. Slowly, but it's still momentum.
- Avoid the YC/HN drum circle. YC would be a ton of fun, an amazing experience -- I'm a two-time reject now! -- but realize that it is a very specific approach to a very specific class of business, that there are a lot of failures and people just don't tend to talk about them much, and that it's far from the only road to success.