Consistency in Communications

Hello, I'm in my late 20s and was contacted by my birth father when I was 25 for the first time. I had found out that my dad who raised me was not my biological father when I was about 15 or 16. There have been many ups and downs over the pasta couple of years as we have gotten to know each other and I have met his wife, his other children, they've visited me, I've visited them, etc. Over the past year or so we strated to form semi-consistent contact, usually a text conversation with him every couple of days or once a week, and I was also in contact with his wife whom I've grown closer to as well. I flew to visit them for a week back in March, and stayed with them during that time. They have a blended family and have been going through a number of tough transitions/ups and downs that many families go through, so it was a busy and chaotic time for them. But I still enjoyed my time there and was glad we had the opportunity to spend that amount of time all together because we live in different states. When I left, both my birth dad and his wife were apologetic that it had been a bit of a strange visit due to things going on in their life with his other kids (his wife is their step-mom). After I visited, I didn't hear from my birth dad for nearly two months. I wasn't sure what was going on and didn't want to bother them but after the weeks went by it felt strange and really started to hurt. I finally broke down and texted him a full two months after my visit, and didn't receive a response for a day or two (this is unlike him and not typical of our past communications) At some point during those days I texted his wife and asked if everything was okay because I hadn't heard from any of them. She responded promptly and the next day I heard from him. He apologized for taking a while to text me back, said things were hectic and that it had been "too long" since we talked. We made polite catch-up conversation. I have not heard from him since then. His wife at one point texted to say that I've been on her mind and that everything there has been chaotic. He hasn't reached out at all, and I have felt a little too wounded to reach out again myself. Father's Day was yesterday. I spent it with my dad who raised me, and I did not contact my birth father. And he didn't contact me. I really don't know what to make of this or what to do next. I feel pretty hurt and am experiencing feelings of abandonment and confusion all over again. I have felt this type of inconsistency from him before. When I've brought it up in the past he generally talks about how busy and hectic things are, but he also always points out that I haven't communicated with him either. It's not that I don't want to make effort here, but it's just hard to keep putting myself out there and then not hearing anything for weeks and wondering why. It brings up a lot of difficult feelings. How to I broach this issue in a way that will not make my birth father mad, have him blame me for not being in contact, etc. These situations are so complicated and I know they wax and wane but I genuinely am at a bit of a loss as to what to do next. Things have felt like they've stopped and started so many times over the past 3 years but I actually thought more recently that things were in a good place, and so this large period of silence has me very confused and upset. Any insights/thoughts much appreciated.