I have become aware that although I do indeed believe and have faith in my true Buddha nature, my divinity (see my post, "Buddhism and the Divine"), and the universe as the source of my supply and that I have been provided with abundance and positive happenstance throughout my life, my ingrained feeling of lack has resurfaced and coexists with this feeling of abundance.
First, some personal history. While I have always been aware of the positive things in my life, both personally and professionally, I have always focused on the things that I do not have. Whether it's the people who I feel don't like me, or my not being popular, for example.
The other pertinent factor is that I have been manifesting things in my life that I would like to be other than they are. These are Right thoughts without which one cannot move forward with one's life. But I have found that as my manifesting has become more specific, more tangible, it has turned into a craving and my mind becomes desperate to have control over its realization. And of course when you feel a craving, you feel the lack of what you don't have.
There are several things I know I must do in my meditation to bring myself back to equanimity. First, is the understanding that lack is not a physical/material fact, it is a perception, it is a label like all other labels. And so as with all labels, I will say to it, "Not me!" (See my post of that title.)
Second, besides saying, no, to my mind, I need to embrace my mind and my inner child and say to them that this is not the way we respond to things and provide them with guidance from my heart, my true Buddha nature. This is a wonderful practice that is full of compassion for myself. (See my post, "Don't Just Say No to the Mind.")
Finally, I must be very clear to myself that I will be ok, safe, regardless what the universe provides, whether what I am manifesting comes to be or not. It would be great if it happens, but if it doesn't, that's ok too. (See my post, "Manifesting in the Moment." For the dangers in manifesting, see my post, "Manifesting - DANGER DANGER!")
It still amazes me, after all the work I've done and progress I've made on the path, that my mind is so tenacious. Worse, it's such a part of my traditional habit-energy that when it asserts itself, I'm often not aware what is happening until I become aware of a problem in my practice.
But now that I'm aware, I know what it is that I must do to free myself from this feeling of lack. As you can see from this and other posts, one's work on the spiritual path is never done.