I don't mean to sound like a sex crazed lunatic but this is making me so sexually frustrated, but lets get one thing straight I'm not a women to leave or to cheat on my boyfriend over lack of sex because sex isn't everything, but when I don't get it I feel desperate and frustrated.
The thing is it's nothing wrong with what I'm doing because I can always make him hard without fail, all it takes is for him to be around me for him to get turned on, this is no problem, but when we go to bed I expect sex not all the time obviously, but I try to make him want it but he sometimes refuses and says he doesn't know whether to because he's too tired then next thing I know he falls asleep but this really does my nut in because I know I can make him hard and want it which turns me on even more! So what's he doing? It's like he ignores his sexual needs he even makes sure that he tells me that I make him hard! I'm not going to make out that we never have it because we do and when we do it feels so good because of a long wait and even he agrees to that! Maybe he likes waiting? Also I'm 19 and he's nearly 25, will he be more calm about this thing then me? It's like I'm constantly horny for him and it gets so annoying sometimes we did have it more at the beginning of the relationship though so I just don't understand what's going on. He often tells me about watching porn and mastubating but this also does my head in as I ask myself questions like what's wrong with having sex with me then? He cuddles me a hell of a lot and tells me he has strong feelings for me so he must love me?
I would be so thankful if anyone gave me some advice on this situation! Because I'm often left awake with thoughts in my head about sex and being able to make love to him and it drives me insane! I'm only human though! Another thing is when we have sex it sometimes doesn't last very long and I'm left unsatisfied, he did used to do stuff till I was fully satisfied after so why not anymore?

Er, have you tried talking about this stuff? Not while you're having sex obviously...

Look - sex is a form of communication and it doesn't sound as if you're communicating with each other very well. You have different expectations of sex and sexual frequency, which is very very common in relationships.

Just because you can make him hard doesn't mean he's interested or willing - as you've found. Also, some guys are actually turned off by women that have a stronger sex drive than them, or who nag them for sex.

You admit you're desperate and frustrated - he may not know how to respond to this and this may make him feel inadequate (rather than turning him on).

I'd suggest it's time to back off a little, do some talking and allow him to take the initiative. Try masturbating yourself a little so that that desperate edge of frustration is reduced, and try allowing the cuddling you do together to naturally evolve into sex.

Relax and chill a little. If you change your approach the dynamic between you will change as well.

He makes a valid point there. If you're tired, then you're not really going to be interesting in sex. There is an easy solution to this. Vary the times you're having sex. Why not have a little post work coitus, or maybe make yourself (or him for that matter) the desert course. It is one of the small issues I have with my GF. We go to bed when we are dead tired. So the chances for sex are slim because one or the other just wants to sleep.

It doesn't take much to get a man hard. The waitress bends over to take your order in just the right way and suddenly his pants are getting tight. Heck I cuddle my GF and my pants get tight.

Could be. Ignites the fires to burn hotter and faster so that the encounter is more explosive. It could also be a variance in sex drives. While you want it so very often, he could not want it so much. It depends on the person to be honest.

Have you asked him? In a non-confrontational manner? Not in the midst of trying to bed him?

Men masturbate. It is a fact of life. He is doing it on his terms when he is feeling it. You could be unavailable at that point. You should ask him.

Can't say. Love is a tricky thing, we can't answer that question for you. Only he can.

If you are really needed satisfaction quickly, go to your local sex shop and get yourself a good vibrator and/or dildo. Get yourself off.

There has been a recurring theme in my post so far. Talk to him. Sit him down and, fully clothed without expectations, talk to him. Ask him what is going on. Express your frustrations. Express your feelings. Ask him if there is anything going on. Ask him if there is an issue medical in nature that he might need to hit the doctor for. Ask him if there is a better time to do this. Communication is the key.

A common adage here is: If you can't talk about sex, than you shouldn't be having sex.

Stop guessing and get answers.