A possible thesis statement about the ability to form stable communities online is: "Although online communities can provide social support and connection for some individuals, the impersonal and often superficial nature of these interactions can ultimately contribute to feelings of loneliness and social isolation."
This thesis statement takes a position on the topic by acknowledging that online communities can provide some benefits, but also highlighting the potential drawbacks of relying on digital interactions for social connection. It also presents the main argument that online communities may not be as stable or fulfilling as real-life relationships. The specific wording and details of the thesis statement can be adjusted based on the specific focus and perspective of the writer.