Happiness is a personal feeling. People around us can create a huge influence to make us happy but the feeling of happiness can only be experienced by us, own. So it wouldn't wrong to say we can create our own happiness. But it's very rare that we try to find happiness in us. It's not a norm of the society too to seek happiness in thyself.
But think this way, when we seek happiness to others, we make ourselves dependent on others, we become fragile to them, they can have control over us and so many things. Is there any necessity to give this authority to anyone when it comes to happiness? You may ask that, what will be our social life then? Shouldn't we care for each other & share happiness? I will say we should and we must. This thing is totally different. We can make others happy and vice versa. But we shouldn't depend on others for our happiness. Especially don't seek that other's will make you happy.
Take the charge of your own life. Be the creator of your own life. It's not always like we can control everything. But we should at least depends only on us when we face some situations.
There's a big difference between taking help from others and taking our own change of life. It's like open towards everyone but being responsible for our ow feeling.
When we learn to build our own happiness, the moment we become more strong. It has a huge emotional effect. Like we know what can we do.
It's like getting emotionally free from everyone. So one can make us sad either. Practicing this in every step of life can boost our self-esteem too. It's not difficult. Just try to be mentally free from the people you think they will make you happy.