The path to success (or a series of successes) is quite bumpy and swirly. Obstacles can seem as intimidating, insurmountable challenges. However, resistance to your pursuits can only mean you are most likely approaching success. The closer you get, the harder it seems. But you know what? As long as you have invested your best effort into something, even if you have a lower than expected result, you have still won, from the experience. In these situations, try to find out [i]why[/i] the result was not as desired. Observe the things you think were lacking and find strategies to polish them for the next time. Don't be shy to fail. On the contrary, talk to your superiors, ask for constructive criticism (what can you do, is it the main thesis or what is it exactly that they found doubtful) - these same people can pinpoint exactly what to work on to improve your results. Every leader is put in situations where he or she had to guess the "right trajectory" of a project completion, the best way to achieve it with the least chances of failure. That is pretty hard, even the best leaders could judge a situation wrongly. Your team trusts you. They wouldn't if you weren't fit to lead. Maybe ask them too about what they think one by one in a team meeting and hear their ideas. Maybe there could be a detail that could help but that you may have overlooked, with all the pressure on your shoulders. If you think you chose wrong, admit it and work along with your team to fix it. Real leaders are not always right. But they have the guts to admit it when they've judged wrong and to move on to solutions. You're just showing that you are human and that you are not there for them only when things are tip-top - you are also there when they flop. That kind of trust is imperative for a good working environment for the group you are managing. They probably feel discouraged by their own performance and may be blaming themselves too. You have to lead by example. When you fall, get up, reassess your strategy and/or your direction and try again. That is how you eventually reach success. You are missing the silver lining: the fact that your research proposal was accepted (even if they were unsure about it) means that you were given a chance to prove them wrong by realizing a fantastic work.

So... my advice would be... seek advice from the ones above you. Or from the academic center, or inspire yourself from someone whose proposal was "perfect". Even if your thesis can be different. Something in someone else's spotless work can help you perfect your own. Find the weak spots they think your proposal has (directly from them, if possible). Figure out how to strengthen those same parts so that your final project can come out well. If nothing works, change your thesis and try again. Nothing shameful about readjusting something that no longer fits. Adapting to unexpected events without losing your resolve is an art worth exercising every day. Again, challenges are a natural occurrence, like the weather... don't allow them to keep you upset or scared. Just live right through them. Every problem has a solution. Keep going you and your team members, until you find it. I believe you can lead and that your team can succeed :)

Sorry you are going through these hard times, I know what that is like.

The advice I can give is you are in a spiral, where you are putting all of your time and efforts into your school work, sacrificing sleep, eating and free time. While I understand doing that, it is counterproductive because you are feeding more and more into the stresses that you are facing. Sleep and eating are vital to recharging your body, otherwise you become more drained and more stressed. Free time to clear your head is important too, even if just 30 minutes to get away from it.

As far as being a leader and feeling like you are failing, that is tough. I would say instead of seeing yourself as a failure, step back, let someone else lead as you suggest. Observe and learn what another person does. Leaders do not always succeed, but what they can do is learn from their mistakes, learn from others and incorporate those into a new style. You are still young according to your listed age, it would probably help to observe. One of your free time activities could be to take some online leadership courses that you can do at your own pace. So you will get a break from studies, at the same time furthering yourself in your goals.

Try not to beat yourself up and see yourself as a disappointment, but as someone that is trying and maybe bit off more than you can handle. Rather see yourself as someone that is putting in great effort but might need help as well.

You had better listen. The only one you need to please is yourself. Learn it now. If not, your life will be difficult always. Just do your best. Become the person you can. Evolve. Your parents should not matter. You are a man now. Be a man. Think. Grow. Learn.

you are good enough, never give up.

Mybe academics isnt your forte