Yeah, there is no denying that bitcoin is the leading coin and will always be in the same position. As we are seeing more and more institutions coming forth in the crypto world, the more power is going to the bitcoin. Eventually, govs will also be willing to accept its power.

Yes, such a phenomenon is present and this is justified if bitcoin is growing, then all the altcoins are behind it, this is explained by the fact that if large investments enter the market, then not only in bitcoin but also in other cryptocurrencies and, accordingly, altcoins are growing

In the cryptocurrency market, the major currency is Bitcoin. Although fiat, Ethereum, and Tether currencies are frequently used.
Altcoin are used to fund bitcoin runs, and Bitcoin funds Alt’s operations. As it relates, movements in the price of Bitcoin are likely
to have an influence on the price of Altcoins. When the price of Bitcoin rises rapidly, the chances are it will depress Altcoins as money
flows into the Bitcoin market. On other occasions, Altcoins will go up, as fiat currencies flow throughout the crypto market, usually,
this phenomenon occurs when a fresh wave of adoption occurs.

Traders and investors will always bet for the safeties of having funds inside bitcoin so they might go around their other funds but there will always remaining in Bitcoin ths is why in each movement alts will always go only once Bitcoin moves first,even if uptrend or downtrend .
But not in 2018 when price of Bitcoin completely going insane but altcoins are doing their trend up,means their supporters can do it after manipulating Bitcoin.
but it is always nice to see the Domino effect of bitcoin  action makes us trust the currency more.

I also see the market is in red. All tokens in my portfolio are in red slowly dropping from 300$ approaching to 150$. Anyway, I'm optimistic that the market will recover again in due time. I'm not so worried of my investment because I know they are potential and can recover again in a matter of time.

That is just the truth and the better most people start understanding that, the better for them. When I say most people, I refer to those who still think an altcoin will overtake Bitcoin or one altcoin is worthy enough to be better than Bitcoin, well I will leave them to that. About the market, it is very obvious that the price of altcoins depends on Bitcoin, and with the increasing rate of Bitcoin's dominance, it further widens that gap and makes them heavily dependent. However, there are still some altcoins that tends to move in relation with Bitcoin, that is, with Bitcoin growth, they also grow with it and vice versa, altcoins such as Ethereum. In the same way, there are a whole lot of others that, once Bitcoin grows they dumps and if Bitcoin dumps, they also dump with it; but in general, Bitcoin dump brings about a big chaos in altcoin market.

It is good if you still have confidence and believe in the market. Many of us doubt that the market will be back soon because we have already seen many corrections since the last months. But we still need to optimist that it is just correction that can happen anytime, and we don't have to worry about that. Everything will be back to normal, and the price will start to increase again. Meanwhile, we can buy more bitcoin again this time before the price break to $19k.

There are times when the market will recover. Pump and dumb are common.
But even so, you must still have a strategy to be able to maintain your investment capital. If the market is bearish and falling beyond our predicted price, we must have spare money to buy back at the bottom price. Do not use 100% of the funds you have. Use about 30% -50% to overcome the shock that will occur.

Staying optimistic and not doing Cutloss will be better than having to panic and end up wasting your money for nothing.

We know all that Bitcoin is a mother coin and it will remain the mother always. We have seen when Bitcoin drop, then at the same time most of the altcoins following the bitcoin trend, but during recovery Bitcoin price most altcoin can't follow the bitcoin trend. That's why sometimes alt traders regret it. I had done the same mistake previously. During trading, I thought my bought coin would follow the trend of Bitcoin. But it didn't happen ever and I lost a huge amount of funds.

In my opinion this is because the Bitcoin downtrend can occur at any time for correction, and cannot be predicted with certainty, so do an accurate assessment and vision every day to ensure an increase in the Bitcoin price, so you can easily take excellent opportunities by buying Altcoins which you think is good and stable for your investment in the market.

Why is it that every time the Bitcoin price drops, the Altcoin market becomes a red zone? because Bitcoin is the heart of all Altcoins, so if the Bitcoin price decreases the Altcoin price will automatically be affected by this decrease in the Bitcoin price.