not like i'm all old and wise, i'm only 21 .. but when i was 17 i had a long distance bf, he was my friend's cousin and lived 5 hours away. we made it work for 3 years and i thought he was the most amazing person in the entire world. until i met my boyfriend now. now i have not one ounce of feeling for my ex. SO just know that u do a lot of growing in the next few years and ur tastes change, ur life changes, etc. so make sure that this is something that u both really want. is it that ur going away to college or something? and u just want her to know that in the end u'll hopefully be together? if that's it .. that's more realistic i think than doing more of a proposal type thing. my friend from college gave his gf a promise ring before they left for school. it didn't mean they were in a committed relationship it just meant that no matter what happened while they were away from each other for 4 years, they wanted to be together in the end. i don't think at 17 there should be any elaborate romantic hoopla. maybe just take her to a really nice dinner and give it to her during dinner! the fact that ur giving her a promise ring to begin with is romantic enough and will make her happy. BUT i will tell u this .. u've been going out for 5 months? is that what it said in the other question u posed? i really would wait until 1 year and do it for a 1 year anniversary. 5 months is not that long, and that way u could use it as her present!