Why is no contact so hard?

Attachment runs on the same reward systems in the brain as other habits we find hard to break. When contact stops, your brain keeps asking for it, loudly, especially at the times you used to talk. The urges are strongest in the first couple of weeks, then come in waves rather than constantly. Knowing that helps. The urge is the habit fading and protesting about it, rather than a sign you should reach out.