Software-Defined Networking (SDN) and Network Function Virtualization (NFV) are paradigms that help administrators to manage dynamic networks. While SDN allows centralized network control, NFV provides flexible and scalable Virtual Network Functions (VNFs). These paradigms are also enablers for concepts such as Service Function Chaining (SFC) where chains are composed of several VNFs to provide a specific service. However, in order to maximize the benefits from the above-mentioned flexibility, new research questions need to be addressed, e.g., regarding effective management processes for dynamic networks. We proposed a novel learning model based on the flexibility of softwarization and abundant volume of monitoring data in NFV environments to predict VNF resource demands using SFC data. Our model is based on Context and Aspect Embedded Attentive Target Dependent Long Short Term Memory (CAT-LSTM) that consists of Target-Dependent LSTM (TD-LSTM), context embedding, aspect embedding, and attention. We developed this model to obtain high accuracy for the prediction of VNF resources such as the CPU. Our model uses two labeling systems: the qualitative resource state and the quantitative resource usage, both of which are used to evaluate its performance. This assists the administrator in understanding the network conditions, improves prediction performance, and provides practically useful information. Our learning model for predicting VNF resource demands can be utilized to solve essential SFC problems such as auto-scaling and optimal placement, which in turn prevent service interruption and provide high reliability.