You are not alone. I have been exactly where you have been. I lost 100 pounds, only to gain 60 of it back. My biological father also died due to his alcoholism and I had mixed feelings about it all and not working harder to rekindle our relationship after meeting him for the first (and only time since I was a child) a few years ago. Now that I have relost that initial weight, I am so afraid some emotional hurdle is going to come at me again, and I will again regain.
The positive outlook on your situation is now you know that you can lose the weight. That really helped me the second round. I had already done it once, so I knew I could again. And, also being aware of how easy it is to pile is great. Now you will know the warning signs and to be aware of triggers.
I like what luckymommy said -- you might be at a much higher weight now if you hadn't lost before...so don't think of it as a failure.