2 of my group members abandoned their work, except for 1 who stayed

I'm so shaken with the way people in my assigned group abandoned me to do the work. It took a last minute added person to make sure I was able to pull through, made a friend out of it too. I'm so deeply thankful they advocated and recognized how much weight pulled on my end. Every other group was given a total of 3 people, ours had 4, you'd think it be easier but it's not when 2 don't pull their weight. I'm still so shakened yet thankful for that added on group member. Would have been stuck doing everything. I learned a valuable lesson from all of this.