Hi Pedro,
After 5 months of hooking up with you, she may have gotten bored.
She may know what to expect and thereby, she doesn’t have the same kind of energy as she once did when she would always be the first to contact you for a hookup.
She may be at a point where she is still unsure of how to go about handling this relationship. On the one hand, she may be thinking about quitting it entirely and on the other hand, she may still want to hold on to it, at least for now, until she finds someone suitable to replace you.
She may be acting really hot and cold towards you because she wants you to do something to bring back the excitement. This may be what she believes she needs in order to get back to how she used to be in wanting to hook up more often.
It may be best for you to try spicing things up.
Be more flirtatious in your conversations with her. Introduce something new to your hookups so that they aren’t always so predictable.
If she is bored with you, spicing things up could make all of the difference.