Keep trying! Just because you have fallen doesn't mean you can't get back up. You are NOT a lost cause just because you are struggling to get to a good place. If you are tempted, and manage to stay away, in that one instance you are working in the right direction. Think of it as a muscle, keep training it to turn away from addiction. God Bless, I will pray for you.

When you say you are “trying” to abstain you have already been conquered. God has promised us today, get thru today and commit to yourself to not do it, not try, do not do it.
If you are around the people that make you want to do “x” stay away from them. You cannot be on a diet and walk into a donut shop.

Seek professional help, professional Godly help.
Prayers for you.