Why pray?

I love this image.
I don't know about you and your theology, but the fundamental God-question I wrestle with constantly is how God works/how prayer works.
I want to thank God for all the good things that happen to me, but I think... if I give God credit for the good things, don't I have a right to blame God for the bad things? But I don't want to do that- and, more importantly, I don't believe (or want to believe) in a God who does things to me, at all- good or bad. I do believe that God could do things to me, or, for me... but I find it harder and harder to believe that He does.
This image is right in line with my thinking. If God isn't going to help these people who are willing to die a very ugly death for Him, why would he give me sunny weather for my day off? He didn't save His own Son from crucifixion... what makes me think He will do my bidding?
But, I want to ask. I want to turn to God and ask for what I need- and Jesus told us to, for crying out loud... I have been told to pray and ask for God's will to be done. Fine, of course I want that (and I always have some suggestions about what God's will should be, in case He's curious) but, how can I think that my prayer will have any effect in God's will? I imagine God's will will be done, whether I pray for it or not. So I pray to God to conform my will to His. So far, I haven't seen much evidence of that prayer being answered in the affirmative.
The parent image is always the one I return to- and use my own parents as models for how it works, maybe. I know they have a will for how I'll live my life, but don't move to control it. I know they love and forgive me when I screw up. I know they would have loved to make my life in their care to be a wonderful, pain-free existence, but that they knew it wouldn't be good for me in the long run to live that way. I know they would love for me to turn to them in my sorrowful and fearful times, even if all they could do was love me through them.
But the problem remains; How to pray?
What used to be long chats with God in prayer come down now to three sentences:
Thank you God. (For Jesus, for my life, for whatever else!)
I love you, God. (because I do)
Conform my will to yours. (just in case)
But when the chips are down (or, the lions released) I still ask for help. I figure if Jesus can ask in the Garden of Gethsemane, I can too... (of course we all know how that turned out)