If you don't trust the man you are with, why continue the relationship... his solar return is about him and how the year ahead will look for him. Since mars is in 8th house he might deal with aggressive debt collectors or he might burn through money as soon as he gets it. I'd advise him not to take out any loans, credit lines etc. as he might have a hard time paying them back. Also make sure he is caution of his surroundings as the 8th house also represent death(figuratively and literally). That doesnt mean he will die violently the year ahead, it could mean he is going to possible need courage to change himself for the better.
His 12th house stellium which contains Neptune, Venus the moon and Uranus makes me believe he will focus much more on 12th house matters. The 12th house represents all things that are hidden from others and sometimes ourselves if we are not consciously aware yet. The 12th house also represents dreams, emotions, our subconscious thinking and psychic powers to some extent. I believe he will have alot of revelations reveal to him whether it's by dreams or premonitions. The 12th house also represents our hidden enemies. Depending on which planet is located in the 12th house, for example he has neptune there so make sure he is careful not to trust people who seem like they will take advantage of him. They could trick or try to deceive him, so it's best he uses his better judgement against people who seem questionable. He also has venus in his 12th house solar return, so he might deal with a secret admirer. That doesnt mean he is going to do anything, he might not even acknowledge it or be aware that someone admires him.
Just remember this is his solar return, his natal chart is his real blueprint in life so try getting a look at you and his natal chart merged together if you feel there is something lacking in the relationship and to help build trust.