Normally bitcoin is volatile, and people think that anyone that they bring into the system to start investments, if the market is bad, they will be worried because they introduced new people to invest in bitcoin, and they think they won't trust them anymore. And when they complained, you thought you forced them to invest. That is not a force, it is a lack of patience. Anyone that is willing to invest in Bitcoin and understand everything will have the patience to invest in Bitcoin for the long term without making unnecessary explanations so that they can probably achieve their goals.
Like some persons already said, you don't force people to invest into Bitcoin. If you carefully teach someone about Bitcoin by completely telling them every important thing they need to know and all the risk that is involved in Bitcoin investment, the person can not blame you for teaching them about Bitcoin, even if price is not favorable to them after they have invested, they will still know that you have given them the important knowledge that will guide them, therefore would know how to go about it. Investing into Bitcoin should be by choice and not duress, and you should not also guarantee anyone profit in Bitcoin, explain the risk to them and let them agree to take the risk on their own.