its natural. like if my ex (broke up last week after 6 and a half months) had something going on with someone else, it would still get to me. even though i've got on 5 people and stuff since.
just remember all the reasons why you broke up, how much of a downer he was. it'll take time, it always does. soon enough you'll look back on this topic and think how silly you were.
you'll be okay :]







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