I think that everyone should do some solo traveling at some point in their life. It doesn't have to be to East Africa like I did, but it could even be to the capital of your state or the closest well-known city that you've been meaning to check out.
The best part of solo traveling is that it forces you to get out of your comfort zone and observe what's around you. When you're with your bestie, you're most likely going to be chatting and pointing out things that are commonly knowned by the both of you, but when you're by yourself, you have no one to compare with except for the locals. You create a new context.
I remember traveling to Italy to meet up with my family for Christmas after my first 6 months in Mozambique. Since I was traveling from Africa, and they were traveling from California, our flights didn't coincide and I got there a day ahead of time.
I checked into the cute hotel/hostel, met the fellow roomies, walked around the city and scoped out the restaurants on my own. I was able to observe and see the beauty of Rome without any distractions.
Yes, it was amazing seeing my family, but that's a different amazing. Both are good :)