This is what the scriptures say on this matter. (D&C 131:1-4) 
 
1 In the celestial glory there are three heavens or degrees; 
2 And in order to obtain the highest, a man must enter into this order of the priesthood [meaning the new and everlasting covenant of marriage]; 
3 And if he does not, he cannot obtain it. 
4 He may enter into the other, but that is the end of his kingdom; he cannot have an increase. 
 
The scriptures make it clear that exhaltation in the highest degree of the celestial kingdom requires this covenant of marriage in the temple. Marriage in the temple is performed by a person who has been given the priesthood authority to bind on earth as well as in heaven. 
 
D&C 132:7 states the following: 
And verily I say unto you, that the conditions of this law are these: All covenants, contracts, bonds, obligations, oaths, vows, performances, connections, associations, or expectations, that are not made and entered into and sealed by the Holy Spirit of promise, of him who is anointed, both as well for time and for all eternity, and that too most holy, by revelation and commandment through the medium of mine anointed, whom I have appointed on the earth to hold this power (and I have appointed unto my servant Joseph to hold this power in the last days, and there is never but one on the earth at a time on whom this power and the keys of this priesthood are conferred), are of no efficacy, virtue, or force in and after the resurrection from the dead; for all contracts that are not made unto this end have an end when men are dead. 
 
This sealing power is only found in the holy temples, and marriages performed outsite of the temples, no matter what intentions or wording is used, can only be "till death do you part." 
 
Now, the good news is that you have time on your side. As you stated, we wouldn't want you to join the church for the wrong reason but we certainly would be thrilled for you to join the church for the right reason. It is wonderful that you are asking questions and trying to learn more. The fact that you have a desire to believe is very promising, that is the beginning of faith (Read Alma 32 starting at verse 27). 
 
You should understand that your boyfriend is about to go through big changes in his life. There is a lot of growing up that happens when a person goes on a mission and he will be a different person in many ways when he gets back. If you love him and want the relationship to last through the mission (much less eternity) you will need to grow with him. This will require lots of personal scripture study and prayer on your part. Read the Book of Mormon and really think about what it is teaching. Pay close attention to your feelings as you read and ponder, try and see if your heart is trying to tell you something. Most importantly, pray to Heavenly Father and ask Him if it is true, and keep praying till you get an answer. When you get that pure testimony that all these things are true, it will ignite a burning desire within you receive all that the Father has in store for you through the restored gospel. The entering the temple will become one of your greatest desires. Then you will be doing it all for the right reasons. 
My challenge to you is to seek for this testimony of the Book of Mormon and the restored gospel, meet and learn from the missionaries in your area, then live your life in such a way that your boyfriend will have to try and catch up to you. Don't be the anchor as you have imagined yourself, be the engine.

Thank you! I have been working on building my testimony. He is out on his mission, and we decided that I would wait for him. I have recently been baptized and it is one of the best decisions I have ever made :) My parents are both supportive of my decision, and I am excited for the future!