As long as we can trust the market we can invest in Bitcoin reliably but when we lose our trust in the market we can no longer invest consistently even if we want to. But at the current level of the market,
If you can't control your greed and emotions while investing then surely you will lose confidence in consistent investing. Because if you are greedy then you can sell Bitcoin when the price goes up a bit. Experienced investors never lose confidence in their investments, they always think positively about the Bitcoin market and they keep their investments for long term.
No, being emotional is for traders, it's either you are a trader that buy and sell at every price increments or you are a long term holder, and as a long term holder you have no business with being emotional because you are only looking at the bigger picture of your Bitcoin investment in like 10 to 20 years time from now, so why would you be exhibiting fear and greed?
Though it's very normal that sometimes you might decide to have a look at what Bitcoin is doing in the market, but you have nothing to worry about because you are a long term holder, it's only traders that exhibit those traits like fear and greed, no an investor.
As for losing confidence in Bitcoin when investing continuously, I don't think it's likely, unless you never have faith in Bitcoin in the first place.