Dear Dr. Wes & Samantha: My boyfriend is really sweet and always nice to me, and we really love each other and I trust him. But we are really different. I’m interested in grades and school and want to be a vet someday. He doesn’t try very hard, doesn’t like school, plays a lot of computer games and smokes a lot of weed. I want to be with him but I want to know if he’ll grow out of this someday or not?

Wes: What do Romeo and Juliet, just about every book by Jane Austen, “Fiddler on The Roof” and “Twilight” all have in common with a thousand other titles I can list? A titanic struggle between the heart and mind in picking a good dating partner. And in nearly every fictional account, guess which wins? The heart. Why? It makes a better story.

Now back to real life. Yours. What should your head be thinking? I have my own little proverb for those wanting better love: Never be in a relationship with someone you wouldn’t consider marrying. I’m not suggesting you seek marriage partners at 16. But your current relationship is practice for what comes next, and a strong predictor of how you’ll couple later on. So practically speaking, is this guy someone you’d want to marry and have kids with? It doesn’t sound like it from your letter. Or if you don’t like that angle, ask yourself if he’s the kind of guy you’ll want your daughter dating in 20 years. I’m guess that’s a big “no” too.

I’m not trying to be the scrooge of love here. Everybody knows I’m a huge romantic. I just think we need to balance all those deep feelings with some practical attention to detail. Why limit yourself to a guy that you JUST love? Why not shoot for the whole deal: Love, ambition, focus on something other than World of Warcraft and pot? You do well in school and have some pretty big goals. Why not expand your horizons a little and shoot for someone who can share that part of your life too.

Finally, you ask that one magnificent question: Will he change? I have the definitive answer: Why wait to find out? I’ve seen a lot of sketchy teen guys and girls turn themselves into pretty great adults. Others don’t get it until their 30s. But quite a few never come around. The question you’re head needs to be asking your heart, is whether right here and now you should spend your time with someone who isn’t really going anywhere. You can always find him 10 years from now on Facebook when it’s easy to see how he’s turned out.

Sure you could tell him your list of must haves and can’t stands, and see if he’ll rise to the occasion. That’s worked for a lot of girls in real life and it always works in great fiction. But while you’re considering that option, think whether you really want to spend your life fixing someone else. Or is it better to find a guy with little or no assembly required? I do believe people change for each other. Otherwise no marriages would ever last. But for meaningful change to occur you have to start with a pretty good core and then work like hell as a team, not you picking at him and him trying to please you.

It’s probably not what you want to hear, but I hope you’ll give this some thought. You’re young. Enjoy practicing.

Samantha: It seems like you enjoy being around your boyfriend and you care about him quite a bit. But, as you perceptibly noticed, you’re headed down different paths. While a friend with a devil-may-care attitude can be exciting to be around sometimes, having a boyfriend with that lifestyle will become more burdensome than fun.

You seem like a goal-oriented, hardworking girl, and having a boyfriend who doesn’t care about his future will be frustrating as you get older. You want to date someone who will motivate and encourage you to work hard, not draw you into a tangled web of distractions. You want to share your dreams him, and hear his in return. Girls mature faster than boys, so in a few years. Wes is right, your boyfriend could turn his life around. He could become a driven, successful guy that you admire.

But here’s the thing: You can’t MAKE that happen. No matter how many times you nag him to put down the video games and start on his homework, you will not get through to him. If he wants to become a different person, you can support him, but it must be his choice. Of course, couples should stretch each other to be better people, but that only works when you start as equals. Think about it like stretching a sheet over the bed with someone. If you pull too hard on your side, their side snaps back in your face.

You don’t want to be a badgering, demanding girlfriend, putting a huge strain on your relationship. I suggest you break up with this guy in a gentle, kind way so that you can still be friends. Tell him you think he’s a great guy and you love to be around him, but you just have different goals, and you don’t want to force him to be someone he is not. Be wary of promises that he will change for you. Say you still want to be just friends, but if you see that he has changed, you would consider dating him again.

Next week: A teen doesn’t want to meet her mom’s new boyfriend.

— Dr. Wes Crenshaw is a board-certified family psychologist and director of the Family Therapy Institute Midwest. Samantha Schwartz is a recent graduate of Lawrence High School. Opinions and advice given here are not meant as a substitute for psychological evaluation or therapy services. Send your questions about adolescent issues (limited to 200 words) to doubletake@ljworld.com. All correspondence is strictly confidential.