Distin handed Liverpool an equaliser before Andy Carroll nodded home a late winner at Wembley.
Howard said: "We were our own worst enemy.
"The disappointment comes from that there was a lot more that we could have done.
"If we could have seen ourselves through the period where Suarez scored, it would have been a different game. We didn't play a whole lot better after that.
"That's when you have to be a man and stick your chest out. We didn't do that and it cost us dearly. Sylvain is devastated, there is nothing you can say that helps someone when that happens.
"It is catastrophic and I have been there. Any pat on the back is in one ear and out the other.
"But he's a man and he will get over it, as will we all."