Darky,

Good to see you talking about serious aspects of betting now.

If you say you are using a solid handicapping method that has proven itself to have an edge long-term, the possible reasons causing you to still lose long-term are:

1) You're not betting just the value selections from the method (eg. you're eroding your value by betting like you did in the example I quoted above)

2) Poor staking/money management

Without knowing exactly how you run your betting, it is hard for me to help. But I would strongly encourage you to do some more research on the above 2 points.

Good to see you're now having a serious go.