Most Helpful Girl
I wouldn't. I'd give it a full year. Just because I feel like that's an appropriate amount of time to re-assess where you are in the healing process. If you completely feel okay about him/her (meaning, you're no longer hurting or angry and genuinely don't care about him/her dating/hooking up with or being in a relationship with somebody) then go for it. But always tread lightly. Keep the conversation very much on the surface. Don't ask too many questions and basically treat it like you're meeting someone new – make small talk and don't assume they're the same as when you were with them. They could have new interests and hobbies. They could be a significantly different person by now. Especially with you being under 18 (if he/she is in your age bracket).
Either way, good luck to you. Dealing with an ex is complicated and it's never simple no matter what.