One of the biggest attachments is the attachment to one's own spiritual gains. In other words; perhaps the greatest attachment one can form is to the idea of themselves as someone who is 'free from attachments'.
What did Marpa say when his son got killed, and his students asked him
why he was crying, wasn’t it all just an illusion? Marpa said
something like “yes, but this is a super illusion.”
It is a trap to imagine that one can be free from attachment in a way that doesn't include the freedom to be attached. To resist attachment is a snare that will bind you tightly (I speak from experience) - being aware of one's attachments, and letting them be is an access to freedom.
There is a reason why asceticism is known as an unsuccessful path. The ascetic has separated himself from human problems to some degree - but only by attempting to become superior to them. He/she finds themselves in a situation where they have conquered some of their sensory desires and attachments; yet they are attached to themselves as the one who is superior.
Chogyam Trungpa talks about this sort of egotistical superiority in his work, "The Myth Of Freedom". He states that this attachment exists within the realm of the gods. Here is some of what he says.
The realm of the gods is realized through tremendous struggle, is
manufactured out of hope and fear. The fear of failure an the hope of
gain builds up and up and up to a crescendo. One moment you think you
are going to make it and the next moment you think you are going to
fail. Alternation between these extremes produces enormous tension.
Success and failure means so much to us―'This is the end of me,' or
'This is my achievement of ultimate pleasure.'
Finally ... a breakthrough, such a tremendous achievement. And then pleasure
begins to saturate our system, psychologically and physically.
[... a lot here ...]
This is the absolute, ultimate achievement of bewilderment, the depths
of ignorance―extremely powerful. It is a kind of spiritual atomic
bomb, self-destructive in terms of compassion, in terms of
communication, in terms of stepping out of the bondage of ego. The
whole approach in the realm of the gods is stepping in and in and in,
churning out more and more chains with which to bind oneself.
The way is something that is designed to rid you of attachment to your own self-importance - to your own superiority and significance. What is critical is to develop the ability to see the world and all its baseness and ugliness, and simultaneously the same baseness and ugliness in yourself, with clear eyes, open and loving to that which is so. As Enyo eloquently states:
If you wish to understand yourself, you must succeed in doing so in
the midst of all kinds of confusions and upsets. Don’t make the
mistake of sitting dead in the cold ashes of a withered tree.
Have room for your attachment, and love it. See it as it is, and give it space to be. Freedom doesn't come from triumphing over attachment, but from being fully human and fully awake to your attachment.