I were in similar situation. I had two shareholders in company that will bring value in the future - that was the hope. They have some skills that I were missing (I thought). At the end I was alone with my product and was stagnating. I decided to ask them to leave the company as I will re-write the product from scratch and make the product core as open source. They agreed to leave the company. Now, I'm 100% solo. Sometimes it is very hard - you even cant talk to anyone. But I know that I'm going to make everything myself or hire a freelancers for help, but I am not relaying on anyone and I think this helps me stay motivated. Having shareholders (or cofounders) that are not shipping regularly with you is very demotivating in my opinion.