How to Cleanse a Heart?

I am still wondering why when everything is going well that I still have wickedness in my heart. I have heard there is a bible quote about cleansing ones heart or something. I need to do that and rid myself of my wicked soul, thoughts whatever is the root of my unhappiness. I wonder why we so often go on self destructive behaviors. I find myself clinging to them like a security blanket and it truly bothers me something awful. I keep fighting them though and I will beat them but will it be to late will I have hurt the ones I love by then or will I finally win. I do not know I can only put my life in Gods hands and hope he can help me find the strength I need to be a better man. I have so much to lose more than I ever have in my life now and this is when it seems to be the hardest to keep the faith. Who knows I do wish I could cleanse my heart and be the man I know I am. Sorry I am just rambling on and on about nothing and everything. I blog I think as a form of venting as well as a way to get feed back but what is funny I never get any feed back I am just not that interesting it would seem lol! Oh well I suppose it is better to be unknown than known on these things. I will continue on trying to keep my heart and self in line and God willing pull myself up out of a potential nose dive. I will do it I always manage to keep it together and I will find a way to cleanse my wicked heart!