dom being hot and cold towards me?

my dom and i have been seeing each other on and off for about 3 years now. we were seeing each other consistently for about 6 months, then just once every 6 months (but texting occasionally), and now we’ve just started seeing each other more consistently again because i moved to the same city as him for school. it’s been amazing and our sessions have been getting more intense, but he’s been really hot and cold towards me and i’m trying to figure out why because i trust him a lot after knowing him for so long. we also have a deep connection with each other and he was the first person i ever had sex with, but he’s older and much more experienced than me, so it’s been leaving me feeling kind of vulnerable and pushed to the side.

some days he’ll text me literally every minute for hours straight until 4am when he gets up for work at 5am, and some other days he’ll leave me on read or delivered for a couple days or be really dry. recently we had an intense session and he gave me proper aftercare and everything, was texting me afterwards telling me he was very proud of me, but now in the couple days after, i asked him when i could see him again and he left me on read. i asked him if i did anything wrong but he hasn’t read it yet, so i guess i’m just making this post to offset the anxiety.

he does work a very demanding job and is often at work from 5am-9pm. he also told me that his friend died recently but that was a couple weeks ago and he wasn’t dry at all around that time. him being hot and cold isn’t exactly something new, i’ve talked to him about this a couple years ago, but he reassured me that it’s because he’s busy with work and even if he doesn’t respond right away, he’ll always respond. i’m trying to be patient and understanding but i also feel especially vulnerable after the last session we had and things we’ve been talking about. in my head i feel like it would take just one minute for him to tell me he’s busy and will respond later, so i guess in my head, i feel like i’m not worth even one minute of his time. has anyone else experienced similar things with their dom??