All Beliefs are Welcome Here!
Did it work?
Find out what you can use as leverage against Mike. While getting rid of him is good, persuading him to work for your benefit is better: the way to persuade him to work for you is to find out what he wants. Ask your shaman friend or another expert what kind of spirit he is, and have them try to confront him to ask him what he wants with/from you. Extract a promise or contract from Mike (it's best if this is written down, so that there can be no shenanigans later) that he either won't harm your daughter or will help you raise your daughter (maybe by giving you hints he's picked up from previous hosts or something). In my experience exorcisms (a ritual which forces spirits to leave a human host) during pregnancy tend to go badly for the mother, the child, or both so that should be your absolute LAST resort (although it may be necessary).
"suppresses my energy or feeds off it from time to time"
You might want to check out
Vampires: The Occult Truth By Konstantinos
Despite the Gothic flare to his work I have found his methods effective for dealing with similar problems.
Ignore the section on Vampire lore and focus on the portions that talk about Psychic Vampirism and Spiritual Vampirism.
The Cleansing ritual in the back of the book is very helpful.
Also The Inner Temple of Witchcraft: Magick, Meditation and Psychic Development By Christopher Penczak
Has a great section on Aura Cleansing and Chakra balancing. Get the CD companion that goes with it as the guided meditations are very helpful when starting out.
Repairing your Aura and cleansing it of negative thought forms is very helpful in getting rid of unwanted company.
There are other books on Strengthening your aura that may be helpful as well. Dion Fortune's book Psychic Self-Defense comes to mind.
Raising your Spiritual Vibrations, Mindfulness Meditation, Dedicating yourself to a god or goddess and most of all disciplining your Mind, Body, and Spirit. Regardless if it is a rouge thought form, mental illness, or spirit, if your do not rule it, it will rule you.
There is no shame in seeing a therapist. I see one every week. She is of the New Age religion but also a licensed hypnotist and therapist. We discuss my Occult practices and beliefs and well... She helps me stay sane. :)
And although there is a stigma around seeing a therapist, I take comfort in knowing that working with a therapist was a prerequisite for Golden Dawn initiates.
And let me be frank, if you are already having this kind of occult related experience, then you need to get your shit together, see a therapist (one who is open to alternative spiritual paths), take up daily meditation, start working on strengthening your aura and balancing your chakras, and perform any banishing rituals that speak to you. Otherwise your condition will worsen over time.
One more thing, and I speak from experience, discontinue immediately any negative spiritual and or mundane practices that are not serving you in a positive way. Search yourself. It will come to you.
Take care brother. Best of luck. Stay sane.
Oh ya and don't forget to laugh at yourself. Laughing at ones self is a very effective banishing technique. Helps keep the ego down. :)
Stop feeding it and if you can't, do a spell to stop feeding it. Other than that if it's real it's probably attached to your spirit in the astral plane, you can do astral magic on it to attack it and pry it off.