What Zaksmummy said.
SFS, we have something in common. I have also contemplated suicide, don't consider myself as worthy and feel that I can't pray right. Sometimes I even begin a prayer with apologizing my weak faith.
You ask: does everyone deserve forgiveness? I don't know. Could I forgive everyone and anyone? I couldn't. What matters is, God's grace through Jesus Christ is perfect. It's perfect and bigger than any of our doubts, any of our sins. It's beyond what we think we deserve. This is what I focus on the Bible, mostly. None of us are perfect. We all sin. God, Jesus Christ and Holy Ghost - they are perfect. Jesus was perfect for us, because we as human beings cannot be.
You say you want to be better. That's a good thing. But if you only want to be better against your conscience and soul just to get some relief from the thoughts of hell, trying to do it like it doesn't feel right, doing it while cringing your teeth, it probably isn't going to last.
Try to focus not on hell, but Jesus, God, love, compassion, forgiveness, grace with an honest and open heart. These things will grow in you. These things will bear fruit. Fear, desperation or excessive guilt that blinds you, are not from God, for God wants you. You are his beloved child, and He is your loving father. Remember - God knows your struggles. He knows your heart. You are searching for him, and you are not doing anything wrong with that.
I struggle a lot with the issues you mentioned too. My depression, anxiety and my own nature sometimes gets me in a dark pit from where I can't see any hope, but just guilt, self-condemnation, shame and darkness. Still, I continue to pray even I feel that God doesn't hear me, doesn't want to hear me for whatever reason that is supposed to be my fault. We need to believe that God's grace is not dependant on our feelings. We need to believe that even if we feel we are letting go, he won't. God is perfect, has perfect love and perfect grace.
I know it is hard, but our own feelings betray us when we are really down.
You, my friend, do not sound like an awful person. You are struggling, and you're having a hard time. Good thing that you go to therapy. If these overwhelming feelings of unworthiness and guilt continue, please be open to any other kind of psychiatric help, too. I've been some times to a psychiatric ward, it has helped through the worst situations. I also had to try many different meds before I found the one that seems to be doing at least something.
SearchingForSalvation, even if you don't feel it now, you are loved. Even if you don't feel it now, you have a lot of love to give, also.
May God be with you, you are not alone.