I haven't seen my husband for 2 months and naturally when we so each other sex was on the brain,however that night he could not get an erection,the subsequent nights we were able to do it with no problems,the last night he had an erection and during intercourse it collapsed,please help.

Are you expecting a different answer by posting this again?

There could be a number of problems. Most are probably non problems. Including performance anxiety.

What sort of person is your husband? Does he smoke? Drink? Healthy? Fat? Any health conditions?

In all honesty you shouldn't make a big deal about this and if your husband is concerned then he should see a doctor. The best thing he could do is see a doctor.