I'm starting to believe that this year would gonna be the year for all altcoins

Let's just be happy about the current price of bitcoin, even if it's down there's still a price in it. Still a valuable assets, although not increasing but maybe we can see an increase but not so huge.
Fully agree with you about this. But if all money come to Altcoin, what will happen with Bitcoin price

take a look at the charts and you will see what happened to bitcoin price!
when bitcoin stops rising and also finished with its big drop, that is when the altcoin rises begin. if you see the chart, when the chart turns into a (nearly) horizontal line the massive altcoin pumps begin and each time bitcoin goes out of "horizontal-mode" then altcoins are abandoned for bitcoin once again.