Hello Cgurl, welcome to the forum. I have bipolar 2 and I'll have a go at answering your questions, though I'd preface my response by making the point that no-one has a crystal ball, regarding bipolar, marriage or life generally.
In looking to decide if you should marry a bipolar person, I'd suggest you broaden your thoughts as to how you would cope with any person, because even the most 'normal', mentally healthy people can change over the years. Without wanting to sound too negative, we do have a high divorce rate in Australia, and not all divorced people have a mental illness.
Anyway, to your specific questions about bipolar:
1. The project mode comes and goes. There's no predicting its frequency. With kids, you can try to get them involved in dad's projects if he's willing. If he's not, then I guess you would have to handle it the same way you would if you married a non-bipolar footballer, golfer, model train enthusiast, workaholic etc. At least when a bipolar person goes into project mode you know why it's happening, and that they're not just avoiding you.
2. Bipolar people tend to want to leave relationships for two reasons. One is that they are in a hypersexual episode. I have never had this, nor have most of my bipolar friends. But if your partner goes through this or you feel he might, talk to him about it! Again, at least you'll know why. Many many non-bipolar people have affairs too - same risk.
The other reason bipolar people tend to want to leave a relationship is because they feel their partners and families would be better off without them. They feel they are inflicting the pain and struggle they are experiencing on their families. A bit like someone with cancer might feel perhaps.
3. Medications can lose their efficacy over time, but this is not always preceded by an event, more likely a change in our mysterious brain chemistry. So there's no way you can plan for it. But do know that having to change medications can be hell, and we need loads of support and understanding when that happens.
4. From my own experience only, I would say yes. But then again, any person, bipolar or not, can become a problem drinker etc at some time in their life. Again, at least you'll know why.
5. Do you really love this man? In sickness and in health? Can you enter a marriage with anyone without an iron-clad guarantee they'll always be healthy, faithful, and present for you?
Are you willing to support him through his struggles?
Regards
Kaz
