How do I reach out to my friend after 2 months of not replying to her texts?

So, I’m a terrible texter. I don’t know what’s wrong with me but I have always really struggled knowing I have messages to respond to.

In this instance, I was texting my friend at the beginning of July. She followed up with some questions and I then went on 3 vacations that month. By the time I was home in early August I thought it was too late to follow up. I kept avoiding replying as the longer time went on the worse I thought it would be.

What do I say to this friend? I’m seeing her next week with the wider friend group but I feel awful.