These are called "wilderness" times. While God is ever-present and able to hear every word we speak to Him, He does, on occassion remain silent. He does this with purpose. He wants YOU to press into Him, spend more time in worship, more time in His word, more time meditating on His character and attributes. In doing these things, you will come into a greater understanding of WHO He really is. Ask Holy Spirit for revelation understanding as you press in.
Maggie
PS...this IS a good thing. Don't waste it by letting any self-pity eat away at you.