› firstname.lastname@example.org 
My boyfriend and I are in our late 20s. He's unable to have sex more than once a day, nor does he want to, even when we've been separated. He can't get it up again even hours later, though we rarely try. He isn't interested as often as I am in general.
My other lovers were often rarin' to go soon after, or at least interested. My impression is that this is normal, particularly for young men. He's unconcerned, but I feel rather unsatisfied and worry that with age his desire will further decrease. He's also very slender and often lacks energy in general. I'm worried something is amiss hormonally or otherwise, which he dismisses. He's had maybe one medical checkup since we met and doesn't get much exercise.
Am I right to be concerned or is this normal? Am I selfish?
Your boyfriend appears to be what they used to call "neurasthenic" rather languid and wan, with a nervous temperament and a tendency toward fainting spells and melancholy. Back then, he would have been fed beef tea and lightly poached eggs on toast and sent back to bed (alone!) to sleep it off for a month or two. Sadly, this sort of rest cure is no longer available to us, so we must make do with modern substitutes: Jamba Juice and gym memberships. He really does sound somewhat undernourished, and I bet you're right about the exercise. Take him out for hamburgers or something. Walk there, if possible. Perhaps if he got his blood pumping on occasion, other forms of pumping would ensue.
There is, inconveniently, no good reason to believe there's anything wrong with him that could be fixed with, say, giant injections of manly androgens. While it's possible that his lowish libido is a hormone thing, it isn't particularly likely. My best guess is that he's just different from (some) other guys and different from you. You probably needn't be concerned about him dropping dead from whatever's keeping his libido low, but you might spare a little concern for yourself and your future. You're not being selfish this is serious. It's likely to be you doing the compromising, so make sure you can before you promise anything permanent.
Couples perfectly matched in appetite are fairly rare, actually. Most people are adjusting a wee bit up or down all the time, depending, and it's hardly worth noticing until it gets to be like one of those science fiction plots where one person's running superfast and the other's in normal time and they can't see each other. We must resist the temptation to declare our partners functional or deviant by the degree to which their sexual desires match our own. Nor does it matter if he's "normal" by others' standards. He's fine for him. It's up to you to decide how fine that is with you.
I'm currently taking a selective serotonin reuptake inhibitor called citalopram (a.k.a. Celexa), and I can't have an orgasm. My sex drive is low compared to normal but not nonexistent. With my boyfriend in my bed, I can still get turned on. And I can get so close to orgasm it feels like it must be about to happen, but somehow it never does, no matter how hard we both try. It's immensely frustrating.
I considered stopping the medication, but I've tried numerous antidepressants, and this is the only one that's allowed me to lead a normal life. I'm reluctant to sacrifice my mental health for my sex life, but I hate having to choose between the two. Can you help? Maybe your readers have similar experiences or some way to get round this?
So frustrating. I think you're right to rank your general mental health above your sex life, but then again, a rotten sex life when you used to have a good one is pretty depressing in itself. On top of that, there are armies of people in exactly your situation with no definite fix, so aaaarrrgh.
I've got three semi-half-assed suggestions; I wish I had a better one. The first is patience, since the side effects often wear off with time. The second is Wellbutrin, either alone or in addition, which is the solution for a lot of people, but I fear you may already have tried it. And the third involves getting various degrees of weird. You could apply something or take something to increase clitoral sensitivity (provided you're a girl; you actually didn't say). Maybe a pump or other sensitizing toy? Or Viagra (they still say it doesn't work for women, but many women disagree), or alprostadil if you can track any down? And then there are creams containing L-arginine or some such that purport to aid arousal and who knows? They probably don't but occasionally appear to. None of these will hurt you (unless contraindicated for some reason; do your homework), and they won't make you more depressed, so what's to lose?
Anyone had any success with other remedies?
Andrea Nemerson teaches sex and communication skills with San Francisco Sex Information. She has been a theater artist, a women's health educator, and a composting instructor, but not at the same time. She is considering offering a workshop on how to have and rear twins without going crazy, since she's currently doing that too.