Someone said: 'Prayer is like a conversation with a friend.'
No it's not. Unless the friend certainly cannot be perceived with the senses and usually cannot be perceived in any way at all. And unless the friend remains completely silent throughout.
It's OK if one does not sense the presence of God or hear a reply.
Prayer is more like watering a dead plant in the attic and then looking out and discovering that the garden is blooming.
The prayer and the response are in different orders of reality and quite asymmetrical.