Only once have I ever encountered a situation where multiple values needed to be concatenated into one field (in my case, comma separated) and with good reason: it violates the normal form and ought to be rarely done. While there might be a good reason as to why you must do this, it's not evident in your posts.
If you have far too many unique values to transpose into fields/columns, then I believe the only solution will prove to be a vba procedure that iterates over a table/query/recordset and appends every value related to the primary key into a new field.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.