It is crucial to realize that gaining an excessive amount of pornography and cyberspace ultimately results in being desensitized, and it has a negative impact on sexual encounters with real living partners and relationships.
The "flat line" effect, that you brought up, is also a commonly displayed problem where former porn addicts may experience a drop in their sex drive and arousal. But for now, the findings are not substantial, more studies are required to distinguish porn effect on sexual function from its own.
With regard to facilitation, many people have found it immensely helpful to consult a professional mental health care provider, such as a therapist or a counselor, and avail their expert help in dealing with this problem and addressing any underlying psychological factors. A sex therapist may possess skills in counseling individuals with sexual dysfunction or enhancing sexual functions.
Your well-being is of top concern and seeking the help of a mental and sexual health specialist can provide you with the needed information when making a decision about your next step. In this connection, I suggest you talk to a psychologist or sex therapist, whose main professional concern is the issues you are experiencing, for more help and support.
Best regards,
Dr. Madhu Sudan