Hi. Hugs.
I have been with my DH for about 10 years also and we have similar problems. DH is very quick, 1-2 minutes and his done. Doesn't discuss things - shuts down, but thankfully does not get mad, cannot get a word out of him.
About a year ago he went to the doctor and was prescribed an antidepressant that is supposed to help with premature ejaculation as a side effect. Sometimes I can tell he lasts longer, but not always. I don't know if he is taking this medicine or not. I have just learned to live with the shortness of the intercourse, and I am ok with it. I have noticed that sometimes if we have sex two days in a row, rare for us, then the second day he would last a little longer.
This is a great board and I have gotten some really good advice here. Stick around and may be you will find something useful for youself.