I am so sorry you're having such trouble with penetration. I found it very painful too the first year or so I was married.
Your husband is getting frustrated, so he must not realize HE can do a lot to make things better. For one, he can read "She Comes First" about how to get you truly ready for penetration and how to bring you enjoyment so you'll actually get something out of the sexual act. For two, most women don't generate the natural lubricant that makes sex easier unless the man has been good and loving to them. Husbands complain all day long, but never seem to realize that step one is treating their wives better!
I was married for over 10 years and never got enjoyment out of sex for three reasons:
1. I had been abused as a child and had no arousal until the Lord delivered me of that hurt.
2. I needed to learn my body.** A woman's body doesn't work like a man's and many men get angry because they expect a woman is like them - couple of rubs and he's done. Well, she's not like him. Her body takes a lot more work to get sexual enjoyment and what works for her can change from day to day.
3. My husband was mean to me, and that dried up all of my arousal. For awhile I thought I was dysfunctional because even after the Lord healed the hurt of my childhood and I began to feel arousal, it would rarely come from my husband. The few times I'd feel aroused were when some other guy was nice to me. I'd have to stay away from that other guy and pray and fast for those feelings to go away so I wouldn't risk falling into adultery.
Finally I figured it out! IT was because he was so mean. He would only be nice when he thought about making love. He would read an article that says "women are like crock pots, it takes them all day to heat up" so he would say he loved me in the morning and send me an email at lunch. But woven around those things was an air of disrespect and an obvious "I'm only saying/doing these things because I want to make love tonight," which totally had the opposite effect: it made me LESS interested in spending that time with him.
I wish more men figured out that if they would treat their wives lovingly that even if she weren't into lovemaking herself, she would be more likely to want to please him in that area.
**Also, the reason I learned my body in the first place was through reading "Woman's Orgasm" which outlines a plan for helping women have one if they never have before. There's some things in that book I don't like (as a Christian - for, example, thinking of a hot star while exploring yourself...that just sounds adulterous to me), but you can skip over steps you don't like and still get a lot out of the book!