It is much easier and more fun to live near each other than to live far away. Spontaneity is a joy of relationships, but when you're 70 minutes apart it gets replaced with scheduling. Here's one simple statement that sums it up: anything you do with long-distance dating, you could also do with near-distance dating (video chat, calls, mailing letters, etc).
Sarah and I long-distance dated about 8 months before engagement (another 3 months after). I think the big turning point was when we both prioritized our relationship and when we worked at communication.
Both Prioritize the Relationship
If you want a flower to grow, you need to water it daily. Same thing with a long-distance relationship. If you say "I'll call my girlfriend tomorrow, today I'm busy doing XYZ", that's a great example of putting someone on the backburner. Instead you gotta commit to growing it and giving that other person some special time. Face it, you probably waste more than 10 minutes a night on Facebook. You DO have time to call.
I would bet most people don't jump into a relationship with both feet. Rather, they keep one foot back for an easy exit as a form of self-defense, saying "if things go wrong, I wasn't really emotionally invested, so it's no big deal." At some point, you gotta jump in.
Both Work at Communication
The best advice we received was simple: have a phone call every day. 10 minutes, 90 minutes, whatever. Just agree to talk every day and ask about the other person's highs and lows. You learn a lot about someone listening to their emotional moments and achievements, and it lets you connect with their day even if you're miles apart. At the end of the call, decide what time tomorrow's call will be.
This alleviated one other major stressor: text messaging. Instead of randomly or robotically sending a "How's your morning going?" text and risk getting no answer for hours (ack!), a 1-word answer (ummm ok?) or any other easily misunderstood message, we KNEW that a phone call was coming up and we didn't have to feel pressured to check in.
Everyone's situation is different, perhaps this isn't a universal answer. I personally would have been OK talking to Sarah every 3 days while Sarah felt a much greater pull to talk daily (due to her love language and personality). She wasn't wrong to want so much, this is who she is and I needed to acknowledge that. So we asked our friends for help and decided to grow closer and stronger together.