My past experience is different than yours, but may be of some help, insight, or I don't know, just commisseration, maybe. My circumstances were my partner took a position that put him away from the house on average of 2-3 weeks at a time then 2-3 weeks at home. I had (at that time) 2yo DS and was pregnant.
Routine was key for me! We had the same bedtime routines, mealtimes, etc whether Daddy was home or not. Also, I put him in a playschool for a couple hours 2 days a week. This was vital to me! I found a place that was affordable and let me choose when he was there (it was the same 2 mornings every week). I needed that time to myself to recharge. A lot of times I went back home and just relaxed. I needed that time to recharge because I didn't have DP there to let me get a break sometimes.
If an activity came up that we would normally go to as a family, we would go whether or not DP was with us or not. It was great when he was with us, but I was not going to miss out on something or have DS miss out just because DP could not be there. On the flip-side, DP also got to do things/have experieces that DS and I did not, because we were not where he was.
One thing I really had to work at sometimes was consistence. He could really test boundaries sometimes, and I had to make sure my responses were always consistent. That was hard sometimes because DP wasn't there to help, other times because DP was home and he wanted Daddy's attention because he had been away. I found the more consistent I was, as in the same reaction every time to whatever situation I was dealing with, the easier things seemed to flow. But, maybe I'm wierd or something, this seemed to be really really difficult when he was coming in and out every couple of weeks...like we always had a few days that were just kinda chaotic whenever he'd leave or come back...it was just hard cause when he'd leave I'd miss him and kinda feel worn out cause he wasn't there to help, and when he'd get back we'd want to spend more time together and slack off a bit on routines which could make things crazy.
I don't know if any of that will help you, but it's a couple things I can think of off the top of my head. This was 12years ago...