Sex dreams. We've all had them and we've all felt the acute panic after a weird one.

Rarely is your after-dark dream world reflective of exactly what's happening in your real life and most of the time you wake up thinking: "what the actual eff?" or "do I fancy my mate?". Even a casual: "do I want to bang my friend's dad?!"

So, we asked dream expert and bestselling author of "The Love, Sex & Relationship Dream Dictionary", Kelly Sullivan Walden to decode a few of the most common dirty dreams and tell us what they really mean. Her insights below...

what it means when you dream about cheating on your partner with someone you know

Kelly Sullivan Walden: In general, if you dream of cheating on your partner, this could indicate dissatisfaction in your relationship and a desire for variety, adventure, and sexual stimulation that you're not finding in your present love affair. This dream could represent your internal struggle with loyalty, guilt, shame, and commitment issues.

If you dream of your lover cheating on you, you may be processing feelings of insecurity, inadequacy, and prompt you to think how you might weather the storm should it actually come to pass in waking reality.

Regardless of whether the person you cheat on in your dream is a stranger, ask yourself what this person represents to you. In other words, are they charming, handsome, risk-taking, sensible, adventurous? Consider these may be qualities you desire but, haven't (yet) given yourself permission to express in your own life.

what it means when you dream about cheating on your partner with a stranger

Kelly: If the person you are cheating on is a stranger, it may be a message that you are wanting to explore outside your comfort zone, as in try a new position, or approach your familiar lover with fresh excitement, as if it were a foreign affair.

what it means when you dream about having sex with a friend

Kelly: Remember that dreams are symbolic and not literal, and they are a symbol for intimate connection. Did you recently have a fight with this person?

Joining with him or her in your dream could be symbolic of reconciliation, empathy, or merging with and understanding their point of view or the qualities they represent.

what it means when you dream about having sex with your ex

Kelly: If you dream of sex with an ex, it doesn't necessarily mean that you long to be with that person. Such dreams are often an attempt to retrieve energy, power, or an important aspect of yourself that you may have left behind with your ex, perhaps a part of your heart you feel is missing.

Consider that your ex represents an aspect of you and it is now time to embrace it in order to become more powerful in your current life and in the relationship you are now in.

what it means when you dream about watching yourself have sex

Kelly: Watching yourself have sex would be about gaining objectivity, appreciation, and/or clarity about your sexuality. Often dreams show us what's in our blind spot, so, this dream may be showing something you've missed, something to change, or something to explore in waking reality that would've never dawned on you normally.

what it means when you dream about watching someone else have sex

Kelly: If you are watching a sexual act in a dream, this may reveal your aloof, detached relationship strategy: being more comfortable dreaming about the relationship of your dreams than realising it.

Conversely, dreams of being a voyeur can help you can gain objectivity about your strategies. Additionally, this dream may be telling you that if you remain aloof in your relationships—avoiding the pain of being on the playing field.

what it means when you dream about having sex with someone you hate

Kelly: If you have sex with someone you dislike or hate, you are working out the parts of yourself that may be sabotaging your ability to manifest the love you desire.

Contemplate the qualities of your dream enemy (cruel, overbearing, critical, selfish) and consider how you demonstrate those qualities in your life, toward yourself or your lover. Once you've explored this, think about alternate, less destructive ways to express yourself and meet your needs.

what it means when you dream about having sex with a gender that you don't think you're attracted to

Kelly: Dreams of this nature represent an intimate joining with the feminine or masculine aspect of yourself. Because we all contain masculine and feminine energy, regardless of our sex.

This could signify your seeking balance, healing of unresolved issues with your same-sex parent, or the freedom and self-love to explore beyond the boundaries of society's expectations.

what it means when you dream about having an orgasm

Kelly: These highly pleasurable dreams are healthy and natural and occur as a result of a lack of inhibition during the dream state. It denotes a sense of fulfillment, wholeness, and awareness of your pleasure principle.

what it means when you dream about getting or giving oral sex

Kelly: Since the penis is the symbol of masculine power and desire, and the mouth is the symbol of communication and self- expression, dreaming of a blow job reflects your desire to communicate what you are passionate about.

This dream can also signify issues of giving versus receiving pleasure. Contemplate any issues you might have regarding the power gained from being in control versus the vulnerability of being out of control. Are you on your knees, showing humility in your relationship? Or does having your most intimate sense of self in the hands and mouth of your lover make you feel vulnerable?

Dreams of cunnilingus describes your connection to the feminine power of receptivity. If you dream of giving it, you may desire to please the feminine impulse within you. If you are on the receiving end, then you may be exploring the depth of your vulnerability in your life. DO you need to be more or less vulnerable?

what it means when you dream about having a threesome

Kelly: Dreams of a threesome signify that you may have split your feelings by falling in love with a person other than your significant other. Or it could suggest that change is in the midst, especially if there is a third-wheel (a person, project, or even work) getting in the way.

what it means when you dream about seducing someone

Dreams of a being seducer or seductress symbolises sexual desires, manipulation, and short-term ego tricks to gain momentary power.

This dream may be an opportunity for you to think about a struggle you might be having with what you want versus what you know is good for you.

This article was written by Caroline Fergusson, and originally appeared on MTV.co.uk. It's been edited for local eyes.