I have a lot of information for you, so put on your reading glasses. You sound so upset over the fact that you aren't orgasming in intercourse. I get the sense that you think that something is wrong with you, and that your boyfriend thinks that he's doing something wrong.
Much of your upset is due to a lack of information. Let me explain. Half of all women never have an orgasm in intercourse. The clitoris has been designed so that it is far enough away from the vagina so that thrusting during intercourse will not provide adequate stimulation.
This is no accident. The female anatomy is wired this way because an orgasm causes vaginal contractions, which expel the semen. Since the survival of the species depends on women becoming pregnant, you can see why nature made it hard for women to orgasm in intercourse. When you understand this, it will be easier for you both to calm down and find a solution.
There are some techniques that can increase your chances of orgasming during intercourse. But don't get down on yourself (no pun intended) if they don't work.
One thing that improves a woman's chances of orgasming during intercourse is to increase the amount of foreplay prior to penetration. If he stimulates you manually or orally (more on this later) until you are almost ready to orgasm, and then he enters you, you may find that the stimulation from thrusting alone will be enough to trigger an orgasm.
You can also try varying your position during intercourse. The woman-on-top position increases the amount of clitoral stimulation a woman receives during penetration.
Adding manual stimulation to intercourse is effective for some women. You said that you aren't comfortable manually stimulating yourself during intercourse. It would be good for you to understand why you are inhibited about this. The more you can loosen up and the more open you are to all kinds of stimulation, the better for you and for your sexual relationship.
If none of these techniques work, remind yourself that you are absolutely fine and in the company of half of all the world's women. What concerns me, most isn't that you aren't coming in intercourse; it's that you aren't coming at all!
If you read over your letter, you will see that you sound selfless to the point of masochism. You allow him to orgasm and don't demand, yes, I mean demand, that your needs are met. You are supposed to have pleasure, and to allow him to get his without you getting yours isn't healthy for you or the relationship.
You say that you are shy about asking for oral sex. You need to understand more about your fear to speak. In order to have a satisfying sex life, you are going to need to identify what's stopping you from taking care of yourself and asking for what you want: Are you afraid to wound his pride by underscoring that penetration isn't a sufficient form of stimulation? Are you afraid that he'll drop you? Or are the fears coming from your own history (you had a selfless mother).
You aren't going to be able to speak with him until you understand what's blocking you from taking care of yourself. When you figure this out, you will be able to proceed.
Let's say you sense that there is a reluctance on his part to give you regular oral sex (you said yourself that he hasn't offered for months). If this is your sense of the situation, then ask the following question,'Why do I feel uncomfortable asking you for more frequent oral sex?' By asking the question, you will open a discussion. As you talk, you will find out if the fear is coming from your own issues or if you are reading him correctly.
Once you start talking, you are on the road to resolving the problem. If it is true that he bruises easily, then explain to him what I told you about the fact that half of all women don't orgasm during intercourse.
I can assure you that this man wants to give you pleasure. He wouldn't be delaying his orgasm if he didn't. If he knew that you wanted more oral sex, I bet he'd give it to you. So tell him that you want oral sex as a steady diet. Then make this part of your foreplay, and see to it that you have your orgasm before he enters you.
When you overcome your fear of taking care of yourself, you assure him that he is a fine lover and that your lack of orgasms in intercourse is normal, he should have no problem shifting his technique so that you have pleasure before penetration.