There;s this belief I hold that there are three types of dreams :: normal dreams (pretty much the average dream scene); prophecy dreams (here your God is directly giving you a message, and you know this though you may need help interpreting the prophecy); and message dreams (where a spirit/dreamwalker is delivering a message to you). I believe your dream may fall somewhere between the first and the third type.

Having your friend shwo up in your dream tells me there is something you are supposed to know or be aware of. Not being able to understand it is simply you not being ready to hear the message. So you go through dream after dream not being ready for the message...then one night you decide to follow your friend. The thing is, to follow your friend requires you to travel into the afterlife. The field may represent this. And then there is the undertone that you have to die to enter the afterlife. Hence the burial. But even in the field, you can't hear the message. This may be because you and your friend are separated by mortal death. I would guess that if this is a message dream you are probably very lucid in it. The next time you have this dream, try asking your friend to show you the message instead of tell you. Perhaps here you can better understand what they are trying to say without fighting the barrier between you. Also, it may be that the message isn't directly for you, but for someone else that you know. In that case, you ay only need to be passing the imagery along for someone else to interpret.