The key to liberation from suffering is not denial. But denial is a tool that one can and should use as part of the overall process of liberating themselves from suffering.
Sometimes we have to deny ourselves certain things in order to build up our tolerance for frustration, physical pain, and other unpleasant realities. Denial can help us liberate our minds. Having said that, we can't deny every aspect of our existence in order to try to achieve some sort of mystical level of enlightenment.
Clearly, we often have to deny certain things that are mentally and physically unhealthy for us. We cannot act on every impulse. If we did, we would do things such as eat candy as our main course at meals, throw things against the wall every time we got frustrated, and kill everyone who was competing for the affections of someone we were attracted to romantically.
You can't deny every aspect of your humanity in an attempt to liberate yourself. You will always have urges and needs that you'll need to respond to. You'll need food, companionship, love, and many other things.
People can become confused regarding teachings about attachments and surrender. Some might think that in order to be enlightened or receive the highest level of consciousness that they’ll need to surrender every single attachment. This is probably not possible, and the pursuit of that level of denial would likely and ironically lead to a greater degree of suffering and confusion than they had to begin with.