I can sympathise with you , it is always difficult when there are problems but it makes it so much worse if you are unable to sleep well, and that in itself is tiring and depressing and you tend to lie there thinking of all the problems and it all mounts up. I have moved 19 times both here and abroad and so have experienced all sorts of neighbours good and bad, so my suggestion for you is one that I often recommend to people in difficult situations.
If you take two pieces of paper and on one write all the things that you like and enjoy about living where you do, and on the other all the things that you dont like . But do it like the old game of consequences. Each time you think of another point write it down on the appropriate sheet and then fold the paper over so that you can not see that reason. Then add more as and when you think of them and again fold them over each time. I would suggest that both you and your husband do your own lists. Let this carry on for a few weeks and then on a quiet day, when you are feeling comfortable , settle down with a coffee and open up your sheets.
You are not trying to make a list but rather look and see the groups that go together, so you would put loud parties and lack of sleep together etc, and on the plus side you may have got your garden to a lovely state that pleases and calms you down. When you have done your own list then look at each others lists. You may be surprised. Whilst you will probably both have very similar points there may be one or two things that you had not considered and it also allows you to see simply what the overall effect the situation is having on you.
From there you might then consider again pros and cons of moving. Do you have many friends and belong to various clubs etc ., and if you moved would you want to remain in the same area or make a total break etc. The thing is that it is unlikely that you can do very much about what they do, but you can make your own plans as to how you will carry on yourselves. Apart from the actual financial concerns on the plus side, you might decide that as you are going to move you would choose a smaller garden or a bungalow or be nearer family or the sea or whatever, which would be a more positive way to think about it rather than they have made you leave. However there is the fact that wherever you go and whoever your neighbours are , peoples lives change and in a few weeks you could end up with totally different neighbours, or the lovely open view you have then be bought for housing and have them building there for a long time etc.
So I think that if you did something on these lines, you would at least then have a clear idea of what things matter to you each, and then you can see what the most important things count and see what you can do to alter matters. You dont mention your ages or if you are retired or anything, so these are other things that might need considering. If you find that you really prefer to stay where you are, you might think it is worthwhile to look into things like changing a window for triple glazing or very good double glazing with a wide gap between the two sheets of glass. This would cut the noise level down. I used to go to Sweden and their good double and triple glazing saved on the cost of electricity, and definitely cut down noise levels. In the meantime as short term ideas, have you found ear plugs helpful? Another possibility is to have headphones with sounds of the sea or bird song , which can be calming and help you to relax a little.
I do not think that "tit for tat" attitudes help but at the same time you are entitled to live your life in your own way too. So if you are an early riser and want to put your radio on at a normal level you should. Out of consideration for my neighbours - I live in a flat - I dont put my radio on at 5am etc when I wake up early and think that about 7.30 or 8am is reasonable and I can here that they are up and moving about. However in your circumstances I would just put the radio on at a normal level, as you are then living your life your way as they live theirs. If they didnt go to bed before 1am that is not your worry. I dont advise you to deliberately do things to annoy them but rather think less about them and more about what you can enjoy in your own life. Do you know much about these new neighbours? If they are still working is it likely that they might move on in a year or two or does it sound as though they are here to stay? One last thing. If you have family or a very close friend or two perhaps they could visit you and hear what it is like . If it has previously been very quiet there and you have got used to that , it may be that your neighbours are not really doing anything unusual or particulary loud or bad , rather that you have got used to the way it was previously, and might be more sensitive to sound now. I hope these ideas might be of some use and at the very least you and your husband will be able to see written down the pros and cons of living there. We dont tend to talk about such things normally, just accept how things are. Wishing you well and hope you find some solutions for yourselves.