Your girlfriend's refusal to make out isn't necessarily your fault. Interactions in a relationship involve the emotional state, physical and mental state of both parties, and the degree of acceptance of intimate behavior, which are complex and multifaceted factors.
First, it may have something to do with her emotional state. She may be experiencing emotional distress such as stress, fatigue, anxiety or depression, which may affect her sexual interest and willingness to engage in intimacy. In this case, what she needs is understanding and support, not blame.
Secondly, it may be a problem with her physical condition. For example, she may be in her period, sick, or unwell, which can make her reluctant to engage in intimate activities.
Also, her personal preferences and comfort are very important. Everyone's receptivity and preferences for intimacy are different, and maybe she just needs more time and space to adapt and enjoy the act of intimacy.
In addition, it may also have something to do with the state of your relationship. If there is a conflict, misunderstanding, or communication problem between you, she may express her displeasure by refusing to be affectionate or need more psychological connection.
In general, when a girlfriend refuses to make out, as a boyfriend, you should respect her choice, understand her feelings, try to communicate openly and honestly, find out the root of the problem, and not simply blame yourself for it. This will not only enhance your understanding and trust, but also promote the healthy development of your relationship.