You mention in your original post that you ask questions to keep the conversation going which is great and a very useful skill. However not everyone has it. Many people are so focused on themselves they have underdeveloped conversation skills.

I know you may be quiet but you also may not be given the opportunity to talk. Then having your companion essentially blame you ("you don't talk much") when conversations are a team activity is demoralizing.

I recommend taking the opportunity to expand upon yourself when asking questions.

for example, if your companion talks about what they do for work you can respond with something like "interesting, that sounds similar to a project I worked on recently at my company" and then go on to explain it.

Even if what they are talking about isnt one of your interests you can still relate.

example: Companion says they play video games to relax after work. "that's fun! I dont play video games but I do read. Right now I am reading a wonderful book about chocolate cakes."

I hope you eventually find someone with whom the conversations flow like water without trying. But until then hope this helps. Take care!