Keep worrying I'm a burden on my gf

We're long distance and she's currently super busy over the summer, so contact hasn't been great lately. Whenever we do talk I worry so much that I'm distracting her or taking her away from something else I can't relax and enjoy it lately. I spend a lot of the conversation in a state of anxiety unless I know for sure she's not doing anything else besides speaking to me.

We've talked/fought about it a bit lately because realistically there's not much more she can do, yet I still feel this way. I hate feeling this needy, and I keep needing reassurance. The worst thing is knowing I'm probably not making our conversations that fun as a result so she's even less likely to want to talk to me now.