A system for detecting online activities associated with a digital identity of a user, the system comprising: one or more processors; memory in communication with the one or more processors; instructions stored in the memory that, when executed by the one or more processors, cause the system to perform: receiving, via a communications network, user identification, User ID, and associated personal identification information, PII, responsive to initiation of identity monitoring enrollment of a user via a user device; extracting, from the user device, unique device identification, Device ID; generating an anonymized digital identification, Digital ID based on the Device ID and the PII, wherein the Digital ID is generated for a user via anonymized PII including alphanumeric identifiers that represent the user; associating the Digital ID with the User ID; detecting, via a Digital Identity Network, DIN, in communication with a plurality of website monitoring application programming interfaces, APIs, executing on a corresponding plurality of websites, an identity-related event corresponding to the Digital ID, wherein the Digital Identity Network, DIN, does not store the PII; determining, using a machine learning model in communication with the one or more processors, whether the identity-related event meets one or more threshold criteria; generating an alert responsive to the threshold criteria being met by the identity-related event; and transmitting the alert, wherein the alert comprises the User ID and identification of the identity-related event. one or more processors; memory in communication with the one or more processors; instructions stored in the memory that, when executed by the one or more processors, cause the system to perform: receiving, via a communications network, user identification, User ID, and associated personal identification information, PII, responsive to initiation of identity monitoring enrollment of a user via a user device; extracting, from the user device, unique device identification, Device ID; generating an anonymized digital identification, Digital ID based on the Device ID and the PII, wherein the Digital ID is generated for a user via anonymized PII including alphanumeric identifiers that represent the user; associating the Digital ID with the User ID; detecting, via a Digital Identity Network, DIN, in communication with a plurality of website monitoring application programming interfaces, APIs, executing on a corresponding plurality of websites, an identity-related event corresponding to the Digital ID, wherein the Digital Identity Network, DIN, does not store the PII; determining, using a machine learning model in communication with the one or more processors, whether the identity-related event meets one or more threshold criteria; generating an alert responsive to the threshold criteria being met by the identity-related event; and transmitting the alert, wherein the alert comprises the User ID and identification of the identity-related event. receiving, via a communications network, user identification, User ID, and associated personal identification information, PII, responsive to initiation of identity monitoring enrollment of a user via a user device; extracting, from the user device, unique device identification, Device ID; generating an anonymized digital identification, Digital ID based on the Device ID and the PII, wherein the Digital ID is generated for a user via anonymized PII including alphanumeric identifiers that represent the user; associating the Digital ID with the User ID; detecting, via a Digital Identity Network, DIN, in communication with a plurality of website monitoring application programming interfaces, APIs, executing on a corresponding plurality of websites, an identity-related event corresponding to the Digital ID, wherein the Digital Identity Network, DIN, does not store the PII; determining, using a machine learning model in communication with the one or more processors, whether the identity-related event meets one or more threshold criteria; generating an alert responsive to the threshold criteria being met by the identity-related event; and transmitting the alert, wherein the alert comprises the User ID and identification of the identity-related event.