There is an element of psyche in a newly married couple; it is a journey of a lifetime with their best friend. This aspect of uncertainty prevails even in duos that have spent fifty years of married life living with their oldest friend. Fights are standard; rough patches in a loving relationship make it more colorful; as the scuffle ends; love begins. These clichés are different from those which cause severe social and romantic life trauma; signs showing the relationship are becoming or always were a toxic one.
No respect and support for each other
A toxic relationship is that bond between two people with no respect and support for each other, conflict is predominant, cohesiveness is absent. While every normal relationship wax and wane, but toxic relationships are persistently horrid, physically, and emotionally draining. Toxic relationships are a potential emotional, mental, and sometimes physical threat to one or both partners. The rage, displeasing moments outweigh the loving, tender moments. If you find your partner has cheated you not once but a number of times and exhibits serial cheater signs, then it is better to quit it than to drag as it causes more pain and frustration.
Sometimes there is only one path left open; to let go.
The deceptive partner intentionally or otherwise wants to harm the other, with a reason behind the action, even profoundly embedded in their subconscious mind. The previous relationship could have been noxious; their upbringing may not have been that loving and supportive. The person may have been harassed in school, suffering from an undiagnosed mental mess like depression, anxiety, or other kind of distress. A woman with a turbulent childhood plunged into a toxic relationship. As a child, she went through physical torture from her father; her mother passed away due to a drug overdose. The marriage also turned out to be that painful; the husband was verbally and emotionally abusive. Sometimes there is only one path left open; to let go.
When both partners want the reins of control in their hands, conflict arises. The chemistry between the duos is wrong; it blazes arrogance and apathy. An empath assumes everyone to be kind-hearted, tolerant; everyone wanted what was best. But the inherent people-pleasing attitude attracts partners who want to control the individual, forcing them to be submissive. The relationship tangles with forcefulness; one tries to appease the other and work for approval, which never comes.
It needs some introspection
The most prominent red flag of a venomous relationship is violence in any form, abuse, or harassment; you must stand up and deal with an iron hand immediately. But human relationships are subtle and intricate. Persistent misery is the foremost and simplest sign of a disastrous relationship. If a relationship always brings pain, anxiety, sad, angry moments, then it needs some introspection. The oppressed partner slowly melts away the self-esteem, feels envious of happy couples, and gradually submerges into depression. This could lead to eating disorders, overweight or skinny, constantly feeling uncomfortable or panicky, especially when the partner is around.
Serial cheaters signs grow up gradually; it changes the relationship as time unfolds. One may feel bad, as one has to appease the other partner all the time, the boundary fade away from an individual self to a person who has given everything to the partner.