"O my God, I cry in the daytime, but Thou hearest not; and in the night season, and am not silent." (Psalm 22:2)
Just...silence. Maybe that's your answer? But how do you feel about it?
One of the hardest things we encounter in life is that feeling of silence we get after we pray. One thing to consider, however, is that you're actually talking to someone. If you didn't believe there was an actual person on the other end, you wouldn't be disappointed by dashed hopes. You'd be speaking into the air, half-heartedly mouthing words to yourself in lieu of actual belief. And Jesus says "be not afraid, only believe." (Mark 5:36) That's the simplest place to start when you need help. And we all need help.
Cri de coeur literally means "cry from the heart". That's what God's looking for in interaction. I don't believe that God is ever silent, but ever communicating. That's one way of looking at it. Even if there is something as silence in interaction, God's "silence" is communication. Either there's something we've done wrong and we're unaware, or there's a depth in us to which God actually is speaking that we haven't reached yet.
When I was in my early teens, I yearned to hear from God. The idea, I suppose, was implanted by my dad. God spoke to him. He got things, he knew things. About me, about life, about situations. God, it would seem, was speaking to him all the time. Oh, he taught me all right. He told me to quiet my heart and listen. Ask God your question, direct to Him a perception or the like, and listen. Even if you forget, God hasn't. And He'll answer in His time.
God hears you. Trust. I think sometimes though, that He wants us to know just what it is we want. A common misperception of Christians is that God already knows what we want, so why be specific? I know I fall into that category at times: "Oh," I wave my hand. "Just do what you think is best, Lord." And God wonders. Give me a good reason. God's willing to do whatever we ask, "if we ask any thing according to His will, He heareth us:" (1 John 5:14) Sometimes our prayers are unformed and lackluster. This is why Paul says this:
"Likewise the Spirit also helpeth our infirmities: for we know not what we should pray for as we ought: but the Spirit [Him]self maketh intercession for us with groanings which cannot be uttered." (Romans 8:26) It's almost as if the Holy Spirit translates our prayers into a language that God understands. And when God speaks, His voice resonates through all dimensions. Time included. The answer will reach you when you're ready.
"And He said, Go forth, and stand upon the mount before the Lord. And, behold, the Lord passed by, and a great and strong wind rent the mountains, and brake in pieces the rocks before the Lord; but the Lord was not in the wind: and after the wind an earthquake; but the Lord was not in the earthquake: And after the earthquake a fire; but the Lord was not in the fire: and after the fire a still small voice." (1 Kings 19:11-12)
A still small voice...
One thing many believers may not consider when they approach God (myself included) is the gravity of the situation. Yes, it says to "come boldly to the throne of grace" (Hebrews 4:16), but do we actually know Who we're talking to? The one who knows the name of every star? The one who named them, no less. The psalmist says "Clouds and darkness are round about Him:" (97:2) That's the One. And if those "clouds and darkness" scare you off, what's wrong? There's a depth to God that we're ignorant of. This is why God looks on the heart. The slightest tincture of belief and pure motive, and love, will in turn move God's heart. He's coming. Trust. All of the crazy activity (the wind, the earthquake, the fire) will subside, and God will answer. A still, small voice. Listen for it.
"The Lord is slow to anger, and great in power, and will not at all acquit the wicked: the Lord hath His way in the whirlwind and in the storm, and the clouds are the dust of His feet." (Nahum 1:3)
"Lord, Thou hast heard the desire of the humble: Thou wilt prepare their heart, Thou wilt cause Thine ear to hear." (Psalm 10:17)