The Buddha taught not all beings could realise his Dhamma because attachment to self is a very strong instinct. Possibly you can ask yourself is Buddhism actually suitable for you? If you realise Buddhism may not be suitable for you, this might help end pride & vanity.
For example, in Christianity, they say the words: "Lord, I am not worthy to receive you. Only say the words so I can be healed". This is said to end pride & vanity, which are one of the seven deadly sins.
Then the thought occurred to me, 'This Dhamma that I have attained is deep, hard to see, hard to realize, peaceful, refined, beyond the
scope of conjecture, subtle, to-be-experienced by the wise. But this
generation delights in attachment, is excited by attachment, enjoys
attachment. For a generation delighting in attachment, excited by
attachment, enjoying attachment, this/that conditionality & dependent
co-arising are hard to see. This state, too, is hard to see: the
resolution of all fabrications, the relinquishment of all
acquisitions, the ending of craving; dispassion; cessation; Unbinding.
And if I were to teach the Dhamma and others would not understand me,
that would be tiresome for me, troublesome for me.'
Just then these verses, unspoken in the past, unheard before, occurred to me:
'Enough now with teaching what only with difficulty I reached. This
Dhamma is not easily realized by those overcome with aversion &
passion.
What is abstruse, subtle, deep, hard to see, going against the flow — those delighting in passion, cloaked in the mass of darkness, won't
see.'
MN 26