That's just the point buddy, just invest what you can afford to lose from your weekly or monthly income then you are good to go, why most Investors are struggling to keep to their investment or keeps on buying regularly is because they are overdoing it more than they can afford, but if it's done with am amount they can do away with and in their own pace, nothing is stopping them from not buying and holding firmly for a very long time.
Bitcoin investment is not gambling that you invest what you can afford to lose. Bitcoin is a reliable asset that has proved over time to be stable and profitable. There should be no doubt or fear in investing in Bitcoin. It would be better to state that people should invest what they can afford to live without. That is, after you have set aside your budget for expenditure and emergency spending, the rest could be easily invested in Bitcoin. There is no need to invest an amount you will struggle to save because there are other important thing to do with money.