I'm sorry for your loss. As a 'tech person' reasonably informed about cryptocurrency, I concur that it is highly unlikely that you will ever recover any money.
Some information about Bitcoin and online scams
Technically, it is not hopeless though. You recovering (some) money would hinge on this chain of events:
- It is not completely impossible that the perpetrators will be
identified. Especially if it can be established that there are a
large number of victims, thus warranting proper investigation resources.
- If they are ultimately identified, it is
possible they will be charged (quite likely in some jurisdictions,
highly unlikely in others, I imagine).
- If they are charged and
convicted it is possible (but not likely) that some of your money
will be returned to you. Again, that probably depends on the
jurisdiction but it also largely depends on how much money can be
squeezed out of them compared to the number of victims.
How to identify the perps?
- It is false that bitcoin transactions are "untraceable". There was a recent global bust related to child exploitation, for example, that was built on bitcoin addresses
- Even if not traceable today, I imagine that in the next decade or two, public resources may make it easy to track down a large number of the more significant-sized bitcoin addresses. What doesnt work today, may still warrant follow up in a few years. Particularly in the case of large accounts
- Information other than bitcoin addresses can also help. They must have had a website, email addresses, maybe they phoned you. Any of those details may, in some cases, help find the perpetrators. It is certainly possible to 'cover your tracks', but not everybody does this and does it correctly.
What you can do
Collect all the raw information (all emails, dates and times, phone numbers or call logs, the bitcoin ATM into which you put your cash or other currency exchange details). Take that all that raw data to law enforcement. Maybe, try various branches of law enforcement. Maybe try to find a way to connect with other victims so that the importance of your case is increased (you would have to contract a knowledgeable programmer to attempt this).
Professional money recovery?
Apparently, there are services you can hire that specialize in this. Some of them seem to imply they don't charge unless they are successful. You might want to spend some time browsing Google search results such as these. I know nothing about these.
Obviously, be very careful since some of these may be tricky (but legitimate) or even fully fraudulent. Some of these may be cynically built on the theory that someone who has fallen for a scam should be easy to scam a second time. But if you can find a service that looks good and you figure out some way to validate it as a trustworthy (maybe get someone to help you with that), it might be worth trying out.
In my opinion these services are, theoretically, not necessarily fraudulent. (How's that for a recommendation?)
All this is probably a lot of work and might even entail more money invested and probably low chance of success. But, given how ignorant most people are about Bitcoin and online scams in general, I wanted to weigh in. If you've got the time and the will, I think you deserve to be able to consider all your options.