I guess the idea of struggling with writing romance is a little weird to me, because I'm a natural shipper; if I really like the chemistry between two characters, I end up writing a romance between them in my head. That doesn't mean I'm good at it; it just means that I tend to do it without really thinking about it. Also, I tend to like relationships that are messed-up on some level, so they're not necessarily the healthiest couple either, but a perfect relationship doesn't necessarily make for a good story.

So I'd look at what dynamics you like in fictional couples, if you don't have a real-life example to draw on. Which characters, if any, do you ship, and why? Are there any romances you've read that worked for you? Examine what draws you to those couples. I'm assuming you're dealing with original fiction, or at least original characters. Don't necessarily rip off canons that you like, but just use them as a source of inspiration.

Another good idea would be to check out blogs that review romance novels; lots of times, the commentary on what they did and didn't like in a novel can give you a good perspective on what works for people and what doesn't.

Finally, I don't know the context for what you're writing, but I wouldn't recommend writing characters around the romance, unless you're specifically writing a romance novel or something. Sometimes things not working out makes for a better story than when things do.

My girlfriend and I were friends for six years, then developed mutual crushes last year, and got together recently. It isn't much different than being friends, and we haven't kissed yet -- we're going slow in the hopes of avoiding the curse of high school relationships -- it's basically a friendship, except with mutual attraction and more physical contact. Things will probably be different if/when we make it to the "fall in love" bit, but it seems to be working for us. :)

(To forestall any confusion: yes, I am a girl.)

I would recommend reading the older classic romance stories (i.e. "Romeo and Juliet", "Pride and Prejudice", etc.). And look into the historical backgrounds of those stories, too.

You will end up using some of the old tropes (it's kind of impossible to avoid all of them), but the trick is to know how to use them properly. You can even play with the tropes a little bit.

Take a look at Fade to Black, and the missions leading up to it. I was basically writing blind, and I still managed to make Valon and Kala starting a relationship look natural.

I haven't been in a romantic relationship either, so like I said, writing blind.