Does God refuse to hear some prayers?

I used to think that God answered all prayers but the more I study the issue the more I become convinced that God does refuse to hear some prayers.  I'll offer a couple of Scriptural references to support that view.  Here is the first one.

Lamentations 3:44-45(NKJV)

    You have covered Yourself with a cloud,     That prayer should not pass through.

    You have made us an offscouring and refuse     In the midst of the peoples.

This seems to indicate that God at time puts up a shield so that some prayers don't pass through.  Now why would He do such a thing?  Doesn't He love everybody? 

Those are good questions.  I believe God does live everybody but God is not an enabler.  What am I talking about? 

We all know enablers.  People who put up with bad behavior in others and then always kowtowing to those people.  Continually bailing them out and helping them not face the consequences of their bad choices or behaviors. 

I am always puzzled by the folks who outright reject God but then turn around in their time of need and expect God to help them.  God seems to address this issue in these next verses.

Ezekiel 14:6-8(NKJV)

“Therefore say to the house of Israel, ‘Thus says the Lord GOD: “Repent, turn away from your idols, and turn your faces away from all your abominations. 

For anyone of the house of Israel, or of the strangers who dwell in Israel, who separates himself from Me and sets up his idols in his heart and puts before him what causes him to stumble into iniquity, then comes to a prophet to inquire of him concerning Me, I the Lord will answer him by Myself. 

I will set My face against that man and make him a sign and a proverb, and I will cut him off from the midst of My people. Then you shall know that I am the Lord.

I may be wrong but here is what this seems to be saying to me.  Those who separate themselves from God by rejecting Him who then look for help from God are just out of luck.  As I've said over and over, God isn't OK with being rejected.  It's not live and let live.  Oh no.  Scripture tells us quite clearly that those who reject God are declaring themselves enemies of God.

Why would God waste time listening to and fulfilling the prayers of His enemies?  An enabler might do that, I don't believe that God does. 

Now does that mean God will never again hear their prayers?  I don't believe so.  The way I understand Scripture, those who are willing to apologize to God and accept Jesus will be welcome back with open arms.  But those who think they can just call on God after they have rejected Him may be a bit surprised at God's response.