Time for some new friends.
There is always an amount of natural wastage when you go through a massive life change. I lost a lot of friends when I had my first baby - they just didn't really "get" that I couldn't be available in the same way (or that drinking for five or six hours is not really a possibility when you are dealing with sleep deprivation!)
But then you also have opportunities to make new friends - antenatal groups, baby groups etc.
During my second pregnancy I had very bad SPD, I can tell you that was a real eye-opener in terms of who my friends were. Some people who I didn't see much of previously really stepped up and were there for me. Others simply vanished. I was unable to walk (or rather, I had to walk because of DC1, but was in a lot of pain!) and it was a really shitty time.
The friends that were there for me through that are the ones I really value now. In some cases they were not even particularly close friends before all that happened. I still don't have unlimited time or energy to socialise but I make an effort to text, email, call as well.
Funnily enough I find myself much less drained by my friendships now. I think a lot of those "fair weather friends" demanded a lot of me without reciprocating. I might go out once a month instead of two or three times a week now, but I almost always come back feeling happy, refreshed, energetic. In the Pre-DC days I often found nights out etc quite fraught and knackering.
Without having a massive fall-out, I would just think about where you want to be directing your time and energy now that it is so precious!