You're getting your life in order. And you should be so so proud of your 3 months sober. But part of getting clean, and staying that way, is making sure you avoid the old people and places where you used before. To stay clean, you have to keep positive influences in your life. The people who want to see you do good and succeed. Those are the people who will help guide you towards a happier life.
I definitely suggest saying no to him and asking him not to contact you anymore. I know it hurts because you guys shared emotions and a history. But he clearly isn't a good influence on you if he wants to ruin your sobriety. He doesn't have your best interests in mind right now. He just wants someone to use with him. Or maybe it makes him feel bad about his life to see you doing so good. Dragging you back to his level will justify his use in some way.
But think about this. About all you had to go through to get clean. And how much damage was caused by using them. Are you ready to let them take control of your life again? And have to go through that struggle again to get clean? You have control here, of your life and what you do with your future. Don't let him and the drugs take over.
Talk to the people in your life you know want to see you doing well. It's ok to lean on them for support when you feel yourself starting to fall. They can help pick you up again. It's ok to admit to feeling weak, we all do sometimes. And then you can maybe plan outings with them to see movies or something. Just show yourself that you can enjoy being sober. And you have people who care a lot about you and your future.
You can resist this. Believe in yourself and don't be too ashamed to talk to those around you about feeling this temptation. They love you and want to help.
Hope this helps. :)
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kid, I wrote back,
all lovers betray.