How to stop thinking about my ex boyfriend?

It's been 4 months since he broke up suddenly. It was a 3 year-old relationship and all gone. His reasoning was how he drifted apart, there is no chemistry, falling out of love and more BS. I believe there is someone is involved.

I can't stop thinking about him. Since Feb, I've been secretly following him in secret, even rode the same bus (but was wearing a black hood and sunglasses to cover myself, avoid getting noticed) after getting off work. I know his schedule and routine by memory.

I'm guessing if I were a guy, this would be crazy. Ok I can't stop thinking about him, getting dumped suddenly and overall getting discarded as if all those 3 years meant nothing. I feel as if I can't stand it if I see him with another girl. He meant so much to me. I continue having to urge to follow him. Any way to get him out of my mind?

How to stop thinking about my ex boyfriend?
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