Sex drives naturally fluctuate, but it can also be influenced by other factors, such as: medication, stress, mental health, and more. One of the most common reasons for libido to dip is relationship issues, but you will be the judge of that.
It’s also normal for a relationship to start out with a “honeymoon phase”, and as time goes on things fall into place and stabilise.
At the end of the day you can’t help not wanting to have sex, and you and your boyfriend might have to accept that and find a way to move forward until your libido increases.