etexas;
I am SO guilty of this: I think of God as if he were a kindly yet forgetful mortal man, by this I mean (as you stated), that he might "forget" promises and Covenants with his Elect. This is a shame to me!
As I said, I struggle with the same thing at times, which is why I have found it helpful to write down the various ways He has been faithful in my own life..it makes it more 'real' for me personally.
I have never met Abraham, though I can read how God remained faithful to Him..I have never met King David, but I can read how God remained faithful to him as well. But, I know me, and as I write down how God has remained faithful to me, I can draw on that as well..
Something else I am noticing is that even in middle of the most trying of circumstances I can begin to see how God is working at answering my prayers.
For example, I have been praying about something for awhile now, I've prayed "God, whatever it takes" I don't know what it's going to take to bring about certain changes to happen, but God does..and as we've been going through various trials, I've noticed minor changes concerning those prayers taking place, and I get excited and start praising God in the midst of it all, and people think I'm nuts and ask me "How can I be praising God that I'm going through this?" And I'm like, well, God is answering a prayer..and they are like.."these events are an answer to your prayers? So, You mean you prayed for this to happen?" and I'm having to explain to them, yes and no.
no, I didn't pray for this exact thing to happen, but yes, I prayed God would change some things..and this is what HE KNEW it would take to bring about these changes even though I didn't, all I know is that I prayed, and this is what God is using to answer those prayers..so I praise Him..and the worry goes away, because I know God is working and I see it..