Ashamedof - have you considered these recent activities as a trap your AV may be setting up for you? If you fast forward to a situation where cheating is a real option for you (i.e. not just looking but alone with someone) it would be easy for your AV to convince you that using would be a better alternative to cheating. Maybe your thought process would be something like "oh, if I don't use I am going to cheat on my husband and that is a worse than using".
I don't have personal experience on bipolar disorder, but cheating is completely incompatible with marriage in my book. My addiction could have been summed up by instant gratification at the expense of long-term consequences. Maybe your just haven't grown accustom to taking things at a sober pace that is devoid of instant gratification. There are few things in life that provide instant gratification without serious, negative consequences.
If you are having trouble seeing things from your husband's perspective (i.e. the severe pain from betrayal), then maybe fast forward things from your perspective. Do you think you are going to be able to cheat and not deal with any consequences if you don't get caught? Imagine the guilt you are going to feel afterwards.
Has your husband been taking care of his "husbandly" duties in the bedroom? If not, maybe try asking him point blank what the problem is. When you are out appreciating the looks from others go buy him a gift instead.