A common situation:
EOS911 may be able to help:
EOS911: an initiative to help EOS token holders who need assistiance with their EOS accounts, whether they have been scammed, or otherwise have lost access to their account
Lost key search with Regular Expressions
All EOS private keys start with a 5 and are exactly 51 characters in length…[search for] any phrase starting with 5 and having 50 characters after it either A-Z, 0-9 or a-z.
Colin Talks Crypto says a solution is in the works: