Karma can be seen through various things. however I’ll start with the Nodes of the Moon.
Any time a planet is conjunct to one of the Nodes of another person, a karmic linkage is indicated.

NN = Northnode – Attracting
SN = Southnode – Releasing

Male NN + Female SaturnNegative for longterm relationships. It creates criticism & obstacles between the individuals. However it’s a good aspect for friends.
Male Saturn + Female SNComes to end past life karma. This aspect creates less troubles in a relationship and is overally good in the Synastry of married couples.
Male Mars + Female NNCreates frustrations and is less beneficial for a love relationship. Good for doing projects together, teamwork since it creates a competitive energy and drive.
Male Mars + Female SNShows lots of fights in the past to repair that anger. This is generally good for love relationships.
Male Sun + Female NNThis aspect brings fascination & generosity. Good for longterm relationships.
Male SN + Female SunAlso brings fascination between two people but might cause frustrations due to the Sun being a masculine planet. Not beneficial for longterm love relationships.
Male Sun + Female SNNegative for love relationships. The male loses his masculinity and may result in lowered self-esteem for him. There is a strong connection of him being your pastlife husband or an authority figure.
Male SN + Female SunThis is a more positive connection since it may lower the masculine energy the female may carry with her.
Male NN + Female MoonA very positive aspect. Loving & nurturing. It gives feminine qualities to the relationship and the male respects her feelings.
Male SN + Female MoonAn indication of one being the mother or wife in a pastlife. But this aspect is negative for longterm love relationships. The feelings are familiar and comforting between you both.
Male Moon + Female NNIf the Moon is waxing than this is a positive aspect.
If the Moon is waning than this is a negative aspect.
Male Moon + Female SNIf the Moon is waning than this is a positive aspect. Increase of sensibility
If the Moon is waxing than this is a negative aspect. Loss of sensibility
Male Venus + Female NNKarmic romance. Needs to learn how to love in a balanced way. increase of harmony.
Male NN + Female VenusBrings harmony, sensuality & pleasure in the relationship. Positive for Love.
Male Venus + Female SNIndication of pastlife spouse. Love & sex are strong in the beginning but it may fade over time.
Male Mercury + Female NNBrings enjoyment, great understanding, friendship, fun & learning.
Male Mercury + Female SNShows you have common interests but this fades over time. Indication of pastlife siblings or neighbors. Excitement fades. Not beneficial for longterm love relationships.
Male Jupiter + Female NNBrings happiness, children & learning. Positive for love relationships.
Male Jupiter + Female SNLessens the prosperity in the relationship. Less beneficial.
Male ASC + Female NNA positive aspect which shows the relationship to have a lasting quality to it.
Male ASC + Female SNA strong connection at first but it may fade over time. Relating less to the ASC person as they grow.

Attraction of Difficult Relationships

Shown by the planets or points located in the same house in the birthchart.

Located in the same house or sign :
Sun + SN, NN, Saturn = Karmic load, difficulties with self-esteem
Moon + SN, NN, Saturn = Unhealthy patterns, addictions, needs are hard to meet
Venus + Saturn = Starved feelings of affection
Venus + NN = Many relationships because you need to learn how to love
Venus + Mars = Arguments, drama & lose objectivity

Sun or Moon Through the houses :
6th house : Arguments, individual allows to be degraded
8th house : Drama, brings sudden changes & difficult experiences
12th house : Loss, distance & low self-esteem

Sun & Moon in the same house or sign :
Makes the individual more emotionally agitated, less flexible

Moon in Scorpio : Creates turbulence in relationships
Sun in Libra : Sense of self-respect may be weak
Sun conjunct Venus : giving more than receiving, relationship problems
Venus opposite/square Pluto : Dominating partner or relationship, obsessive, fear to open up
North or Southnode in 7th : Imbalanced relationship or the absence of one. doing it wrong

Venus in 6th : Arguments, unequality, imbalance in lovelife
Venus in 8th : Creates changes & drama in relationships
Venus in Virgo : To critical or attract love of that nature
Saturn in Angular houses = Creates loneliness & insecurities

Attracting difficult relationships :

• 6th ruler in 7th
• 7th ruler in 6th
• 8th ruler in 7th
• 7th ruler in 8th
• 12th ruler in 7
• 7th ruler in 12th