Responsibility vs. Reliability

I should have figured (when Wikipedia didn't even have a definition) that to write about responsibility might be a murky pond I shouldn't even stick my toe into. However, having a big toe that has it's own responsibility issues drove me forward into the mess that follows.

Lately I haven't been feeling very reliable. I don't return things that I should - emails, phone calls, books, scarves etc. Nor do I show up for people, events or myself like I used to, so I started to wonder about the difference between reliability and responsibility. I got as far as they both start with R and have something to do with the human condition and then got lost.

Reverting to my fondness for actual paper books I looked up in the American Century Dictionary;

reliable - of consistently good character, dependable.

responsible - liable to be called to account, morally accountable for ones actions, of good credit.

Even though these definitions are different, I think in common usage they have melded together and the words are interchangeable. Although I suppose we can have a dependable person who wont take responsibility for him/herself.

I'm in way over my head here, but I need to say I feel I'm responsible but going through an unreliable phase, and that's all the brain power I'm going to devote to that issue.

What do you think - can you be reliable and not responsible or visa versa?