How do they do it?

Ryan is on the annual men's backpacking trip this weekend while I am home with Keegan. Going into this weekend I was apprehensive that I could do this, after the depression diagnosis last Friday at Dr. Inz's office I was almost sure I wouldn't have what it takes.
I started the weekend early, got off at noon on Friday. Keegan's PT got bumped to Friday this week because his therapist had to do some taping for the Easter Seals Telethon coming up in April. We did PT Friday around noon. He did VERY well. Mrs. Patty is VERY happy with how he is doing holding his head up, rotation and even rolling! We have good days and bad though, sometimes Mrs. Patty thinks that he is playing possum.
After therapy was over Keegan and I went to Target, I need to pick up some prescriptions and I wanted to look at the spring clothes for him and I also needed Enfamil.  He slept the entire way through target-PT really worked him out yesterday!
We finally got home at 2:30 and it seems like the minute we stepped foot in the house Keegan just started crying, the crying turned into screaming and for an hour and half I tried everything I knew to calm him down. I got him naked, rocked him, changed his diaper, walked around the house with him, put him in his rocker, laid him down, tired to play with toys with him.......nothing was working.  Finally around 5ish I fed him and he fell asleep on my lap (I think the crying wore him out). We were supposed to go out to dinner with Auntie Laura and Uncie ReXx, so around 5:30 she called and woke me up.
I started to get Keegan ready to go only but when I put him in his car seat he started to scream, bloody curling screams! I quickly text them to let them know that dinner was no longer an option and tried to soothe Keegan. When I couldn't get his calmed back down, I called mom who so graciously came over to help me out. By the time she got here though he was on the verge of passing out again. I turned him over to mom so I could change because by now it was 6 o'clock and I was still wearing my heeled boots that I had wore to work.
I kept thinking to myself this entire afternoon, I have no idea how single parents do it...NONE! I know when I get frustrated I can just ask Ry to take him and I can remove myself from the situation, but when you are by yourself you don't have that luxury......I couldn't  imagine not having a partner to turn to during these trying times, it is days like today it makes me very thankful for who Ryan is and how he is with Keegan and I!