I will be alone again

Seems everytime I allow someone into my life and I get close to them they leave. they disappear. I understand the reasoning for my friend moving but it has seemed since me moving in with her and becoming her roommate she has pretty much disappeared anyways, she has become distanced and has made me feel almost as if i did not exist. Now I feel as if I meant nothing to her. I am lost. I am losing the only friend I thought I had even if I lost her already by moving in with her I am truly losing her now. she is is moving away and leaving me here alone.