These verbs can be very confusing due to their similarities, but they are used differently.

When you end something, you stop doing it, even though it could go on.

                I ended the meeting because it was getting late.
                Mary has ended her relationship with Bob—it was about time!
                I’ll be visiting Taiwan at the end of the month—how exciting!

When you finish something, you complete it, there’s no more to do.

                I finished reading that book you gave me last night—it was wonderful!
                Larry finished the ice cream, so we need to buy more.
                Henry has finished writing the report—do you want to read it?

Now you should be able to keep them separate and not confuse them anymore!